14
Bol. Soc. Mat. Mex. (2015) 21:149–162 DOI 10.1007/s40590-015-0061-y ORIGINAL ARTICLE More properties on multi-poly-Euler polynomials Hassan Jolany 1 · Roberto B. Corcino 2 · Takao Komatsu 3 Received: 23 January 2014 / Accepted: 4 May 2015 / Published online: 20 June 2015 © Sociedad Matemática Mexicana 2015 Abstract In this paper, we establish more properties of generalized poly-Euler poly- nomials with three parameters and we investigate a kind of symmetrized generalization of poly-Euler polynomials. Moreover, we introduce a more general form of multi- poly-Euler polynomials and obtain some identities parallel to those of the generalized poly-Euler polynomials. Keywords Poly-Euler polynomials · Appell polynomials · Poly-logarithm · Generating function Mathematics Subject Classification 11B68 · 11B73 · 05A15 1 Introduction The nature of introducing Bernoulli numbers is parallel to that of Euler numbers. Bernoulli numbers have been introduced by Jacob Bernoulli (1655–1705) in his effort to describe the coefficients of the polynomial representation of the sum B Hassan Jolany [email protected]; [email protected] Roberto B. Corcino [email protected] Takao Komatsu [email protected] 1 Laboratoire Paul Painlevé, UFR de Mathématiques, Université des Sciences et Technologies de Lille, CNRS-UMR 8524, 59655 Villeneuve d’Ascq Cedex, France 2 Mathematics and ICT Department, Cebu Normal University, Osmena Blvd., 6000 Cebu, Philippines 3 School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China

More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino [email protected] Takao Komatsu [email protected] 1 Laboratoire Paul Painlevé,

  • Upload
    others

  • View
    2

  • Download
    0

Embed Size (px)

Citation preview

Page 1: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

Bol. Soc. Mat. Mex. (2015) 21:149–162DOI 10.1007/s40590-015-0061-y

ORIGINAL ARTICLE

More properties on multi-poly-Euler polynomials

Hassan Jolany1 · Roberto B. Corcino2 ·Takao Komatsu3

Received: 23 January 2014 / Accepted: 4 May 2015 / Published online: 20 June 2015© Sociedad Matemática Mexicana 2015

Abstract In this paper, we establish more properties of generalized poly-Euler poly-nomialswith three parameters andwe investigate a kind of symmetrized generalizationof poly-Euler polynomials. Moreover, we introduce a more general form of multi-poly-Euler polynomials and obtain some identities parallel to those of the generalizedpoly-Euler polynomials.

Keywords Poly-Euler polynomials · Appell polynomials · Poly-logarithm ·Generating function

Mathematics Subject Classification 11B68 · 11B73 · 05A15

1 Introduction

The nature of introducing Bernoulli numbers is parallel to that of Euler numbers.Bernoulli numbers have been introduced by Jacob Bernoulli (1655–1705) in his effortto describe the coefficients of the polynomial representation of the sum

B Hassan [email protected]; [email protected]

Roberto B. [email protected]

Takao [email protected]

1 Laboratoire Paul Painlevé, UFR de Mathématiques, Université des Sciences etTechnologies de Lille, CNRS-UMR 8524, 59655 Villeneuve d’Ascq Cedex, France

2 Mathematics and ICT Department, Cebu Normal University, Osmena Blvd.,6000 Cebu, Philippines

3 School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China

Page 2: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

150 H. Jolany et al.

Sm(n) = 1m + 2m + · · · + nm,

while Euler numbers have been introduced by Leonard Euler (1707–1783) in his desireto evaluate the alternating sum

An(m) = mn − (m − 1)n + · · · + (−1)m−11n .

Moreover, Bernoulli and Euler numbers have been usually defined by means of thefollowing generating functions with parallel structures

x

ex − 1=

∞∑

n=0

Bnxn

n! (1)

2

ex + e−x=

∞∑

n=0

Enxn

n! , (2)

respectively. It is worth mentioning that Euler worked intensively on Bernoulli num-bers and gave great contributions in the development of the numbers. This made himknown as “godfather” of Bernoulli numbers (see [5]).

TheBernoulli andEuler polynomials are defined parallel to (1) and (2), respectively,as follows

text

et − 1=

∞∑

n=0

Bn(x)tn

n! (3)

2ext

et + 1=

∞∑

n=0

En(x)tn

n! . (4)

In particular, Bn = Bn(0) and En = 2n En(1/2).In 1997, Kaneko [15] introduced the poly-Bernoulli numbers B(k)

n by means of thefollowing exponential generating function

Lik(1 − e−x )

1 − e−x=

∞∑

n=0

B(k)n

xn

n!

where

Lik(z) =∞∑

n=0

zn

nk.

Ohno and Sasaki [17], on the other hand, defined poly-Euler numbers as

Lik(1 − e−4t )

4t cosh t=

∞∑

n=0

E (k)n

tn

n!

Page 3: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 151

which have been recently extended by Jolany et al. [14] in polynomial form as

2Lik(1 − e−t )

1 + etext =

∞∑

n=0

E (k)n (x)

tn

n! . (5)

One can easily verify that B(1)n = Bn(1), E

(1)n = En = 2n En(1/2) and E (1)

n (x) =nEn−1(x). Further generalization and other properties of poly-Bernoulli and poly-Euler numbers and polynomials including their relations with other special numbersand functions are found in [1–4,6,7,9–13].

In [14], the generalized poly-Euler polynomials with parameters a, b and c aredefined by

2Lik(1 − (ab)−t )

a−t + btcxt =

∞∑

n=0

E (k)n (x; a, b, c)

tn

n! . (6)

Note that, the poly-Euler polynomials in [2,17] can be deduced from (6) by replacingt with 4t and taking x = 1/2. Moreover, when x = 0, (6) gives

E (k)n (0; a, b, c) = E (k)

n (a, b)

where

2Lik(1 − (ab)−t )

a−t + bt=

∞∑

n=0

E (k)n (a, b)

tn

n! ,

and when a = 1 and b = c = e with E (k)n (x; 1, e, e) = E (k)

n (x), we obtain Eq. (5).However, only one identity has been obtained in [14] for E (k)

n (x; a, b, c) which isgiven by

E (k)n (x; a, b, c) =

n∑

m=0

m∑

j=0

j∑

i=0

2(−1)m− j+i

j k

(j

i

)(x ln c − (m − j + i + 1)

ln a − (m − j + i + 1) ln b)n . (7)

In the same paper by Jolany et al. [14], they defined certain multi-poly-Euler poly-nomials as follows

2Li(k1,k2,...,kr )(1 − (ab)−t )

(a−t + bt )rer xt =

∞∑

n=0

E (k1,k2,...,kr )n (x; a, b)

tn

n! . (8)

where

Li(k1,k2,...,kr )(z) =∑

0≤m1≤m2≤···≤mr

zmr

mk11 mk2

2 · · ·mkrr

Page 4: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

152 H. Jolany et al.

is the generalization of poly-logarithm, also known as multiple zeta values, whichhave been given much attention recently but until now, their precise structure remainsa mystery. Note that, when r = 1, (8) immediately yields (6). Several identities onE (k1,k2,...,kr )n (x; a, b) have been obtained in [14] including the recurrence relations

and certain explicit formula. However, this explicit formula is limited only to the casewhere a = 1 and b = e. In this present paper, more identities for E (k)

n (x; a, b, c)will be established and further generalization of E (k1,k2,...,kr )

n (x; a, b) will beinvestigated.

2 Some results on generalized poly-Euler polynomials

The main objective of this section is to establish more identities for E (k)n (x; a, b, c).

First, let us consider an expression for E (k)n (x; a, b, c) in terms of E (k)

i (a, b), i =0, 1, . . . , n.

Theorem 2.1 The generalized poly-Euler polynomials satisfy the following relation

E (k)n (x; a, b, c) =

n∑

i=0

(n

i

)(ln c)n−i E (k)

i (a, b)xn−i (9)

Proof Using (6), we have

∞∑

n=0

E (k)n (x; a, b, c)

tn

n! = 2Lik(1 − (ab)−t )

a−t + btcxt = ext ln c

∞∑

n=0

E (k)n (a, b)

tn

n!

=∞∑

n=0

n∑

i=0

(xt ln c)n−i

(n − i)! E (k)i (a, b)

t i

i !

=∞∑

n=0

(n∑

i=0

(n

i

)(ln c)n−i E (k)

i (a, b)xn−i

)tn

n! .

Comparing the coefficients of tnn! , we obtain the desired result. ��

The next identity gives a relation between E (k)n (x; a, b, c) and E (k)

n (x).

Theorem 2.2 The generalized poly-Euler polynomials satisfy the following relation

E (k)n (x; a, b, c) = (ln a + ln b)n E (k)

n

(x ln c + ln a

ln a + ln b

)(10)

Proof Using (6), we have

Page 5: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 153

∞∑

n=0

E (k)n (x; a, b, c)

tn

n! = 2Lik(1 − (ab)−t )

a−t (1 + (ab)t )ext ln c

= 2ex ln c+ln a

ln ab t ln ab Lik(1 − e−t ln ab)

1 + et ln ab

=∞∑

n=0

(ln a + ln b)n E (k)n

(x ln c + ln a

ln a + ln b

)tn

n! .

Comparing the coefficients of tnn! , we obtain the desired result. ��

Theorem 2.3 The generalized poly-Euler polynomials satisfy the following relation

d

dxE (k)n+1(x; a, b, c) = (n + 1)(ln c)E (k)

n (x; a, b, c) (11)

Proof Using (6), we have

∞∑

n=0

d

dxE (k)n (x; a, b, c)

tn

n! = 2t (ln c)Lik(1 − (ab)−t )

(a−t + bt )ext ln c

∞∑

n=0

d

dxE (k)n (x; a, b, c)

tn−1

n! =∞∑

n=0

(ln c)E (k)n (x; a, b, c)

tn

n! .

Hence,

∞∑

n=0

1

n + 1

d

dxE (k)n+1(x; a, b, c)

tn

n! =∞∑

n=0

(ln c)E (k)n (x; a, b, c)

tn

n! .

Comparing the coefficients of tnn! , we obtain the desired result. ��

The following corollary immediately follows from Theorem 2.3 by taking c = e.For brevity, let us denote E (k)

n (x; a, b, e) by E (k)n (x; a, b).

Corollary 2.4 The generalized poly-Euler polynomials are Appell polynomials in thesense that

d

dxE (k)n+1(x; a, b) = (n + 1)E (k)

n (x; a, b) (12)

Consequently, using the characterization of Appell polynomials [16,18,19], thefollowing addition formula can easily be obtained.

Corollary 2.5 The generalized poly-Euler polynomials satisfy the following additionformula

E (k)n (x + y; a, b) =

n∑

i=0

(n

i

)E (k)i (x; a, b)yn−i (13)

Page 6: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

154 H. Jolany et al.

Taking x = 0 in formula (13) and using the fact that E (k)n (0; a, b) = E (k)

n (a, b),Corollary 2.5 gives formula (9) in Theorem 2.1 with c = e.

Furthermore, using the fact that E (k)n (x; a, b) satisfies the relation

∞∑

n=0

E (k)n (x; a, b)

tn

n! = 2Lik(1 − (ab)−t )

a−t + btext , (14)

and the exponential generating function for Stirling numbers of the second kind [8]

∞∑

n=0

{nk

}tn

n! = (et − 1)k

k! , (15)

we have the following theorem:

Theorem 2.6 The generalized poly-Euler polynomials E (k)n (x; a, b) satisfy the fol-

lowing explicit formulas

E (k)n (x; a, b) =

∞∑

m=0

n∑

l=m

{lm

} (n

l

)E (k)n−l(−m; a, b)(x)(m) (16)

E (k)n (x; a, b) =

∞∑

m=0

n∑

l=m

{lm

} (n

l

)E (k)n−l(0; a, b)(x)m (17)

E (k)n (x; a, b) =

∞∑

m=0

(n

m

) n−m∑

l=0

(n−ml

)(l+s

l

){l + ss

}E (k)n−m−l(0; a, b)B(s)

m (x) (18)

E (k)n (x; a, b) =

∞∑

m=0

(nm

)

(1 − λ)s

s∑

j=0

(s

j

)(−λ)s− j E (k)

n−m( j; a, b)H (s)m (x; λ), (19)

where (x)(n) = x(x + 1) · · · (x + n − 1), (x)n = x(x − 1) · · · (x − n + 1),

(t

et − 1

)s

ext =∞∑

n=0

B(s)n (x)

tn

n! and

(1 − λ

et − λ

)s

ext =∞∑

n=0

H (s)n (x; λ)

tn

n! .

Proof First, we prove (16). From (14) and using Newton’s Binomial Theorem, wehave

∞∑

n=0

E (k)n (x; a, b)

tn

n! = 2Lik(1 − (ab)−t )

a−t + bt

∞∑

m=0

(x + m − 1

m

)(1 − e−t )m

=∞∑

m=0

(x)(m) (et − 1)m

m!2Lik(1 − (ab)−t )

a−t + bte−mt

Page 7: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 155

=∞∑

m=0

(x)(m)

( ∞∑

n=0

{nm

}tn

n!

) ( ∞∑

n=0

E (k)n (−m; a, b)

tn

n!

)

=∞∑

m=0

(x)(m)∞∑

n=0

n∑

l=0

{lm

}t l

l! E(k)n−l(−m; a, b)

tn−l

(n − l)!

=∞∑

n=0

{ ∞∑

m=0

n∑

l=m

{lm

} (n

l

)E (k)n−l(−m; a, b)(x)(m)

}tn

n!

Comparing coefficients completes the proof of (16). To prove identity (17), we have

∞∑

n=0

E (k)n (x; a, b)

tn

n! = 2Lik(1 − (ab)−t )

a−t + bt

∞∑

m=0

(x

m

)(et − 1)m

=∞∑

m=0

(x)m(et − 1)m

m!2Lik(1 − (ab)−t )

a−t + bt

=∞∑

m=0

(x)m

( ∞∑

n=0

{nm

}tn

n!

) ( ∞∑

n=0

E (k)n (0; a, b)

tn

n!

)

=∞∑

m=0

(x)m

∞∑

n=0

n∑

l=0

{lm

}t l

l! E(k)n−l(0; a, b)

tn−l

(n − l)!

=∞∑

n=0

{ ∞∑

m=0

n∑

l=m

{lm

} (n

l

)E (k)n−l(0; a, b)(x)m

}tn

n!

Again, comparing coefficients completes the proof of (17).The proofs for identities (18) and (19) are left to the reader. ��Now, let us consider the following definition which contains certain symmetrized

generalization of poly-Euler polynomials with parameters a, b and c.

Definition 2.7 For m, n ≥ 0, we define

D(m)n (x, y; a, b, c)= 1

(ln a + ln b)n

m∑

k=0

(m

k

)E (−k)n (x; a, b, c)

(y ln c + ln a

ln a + ln b

)m−k

.

(20)

The following theorem contains the double generating function for D(m)n (x, y;

a, b, c).

Theorem 2.8 For n,m ≥ 0, we have

∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m! = 2e

(y ln c+ln aln a+ln b

)ue

(x ln c+ln aln a+ln b

)tet+u

(1 − e−t

)

(et + 1)(et + eu − et+u). (21)

Page 8: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

156 H. Jolany et al.

Proof

∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m!

=∞∑

n=0

∞∑

m=0

1

(ln a + ln b)n

m∑

k=0

E (−k)n (x; a, b, c)

(y ln c + ln a

ln a + ln b

)m−k tn

n!um

k!(m − k)!

=∞∑

n=0

∞∑

k=0

m≥k

1

(ln a + ln b)nE (−k)n (x; a, b, c)

(y ln c + ln a

ln a + ln b

)m−k tn

n!um

k!(m − k)! .

Replacing m − k with l and using Theorem 2.2, we obtain∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m!

=∞∑

n=0

∞∑

k=0

∞∑

l=0

1

(ln a + ln b)nE (−k)n (x; a, b, c)

(y ln c + ln a

ln a + ln b

)l tn

n!uk

k!ul

l!

= e

(y ln c+ln aln a+ln b

)u

∞∑

n=0

∞∑

k=0

E (−k)n

(x ln c + ln a

ln a + ln b

)tn

n!uk

k!

= e

(y ln c+ln aln a+ln b

)u

∞∑

k=0

2Lik(1 − e−t )

1 + e−te

(x ln c+ln aln a+ln b

)t uk

k!

= e

(y ln c+ln aln a+ln b

)ue

(x ln c+ln aln a+ln b

)t

∞∑

k=0

∞∑

n=0

E (−k)n (0)

tn

n!uk

k! .

Note that∞∑

k=0

∞∑

n=0

E (−k)n (0)

tn

n!uk

k! =∞∑

k=0

m>0

2(1 − e−t

)mmk

1 + etuk

k!

=∑

m>0

2(1 − e−t

)m

1 + et

∞∑

k=0

(mu)k

k!

= 2

1 + et∑

m>0

(1 − e−t)m emu

= 2

1 + et

(1 − e−t

)eu

1 − (1 − e−t

)eu

= 2et+u(1 − e−t

)

(et + 1)(et + eu − et+u).

Thus,

∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m! = 2e

(y ln c+ln aln a+ln b

)ue

(x ln c+ln aln a+ln b

)tet+u

(1 − e−t

)

(et + 1)(et + eu − et+u).

��

Page 9: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 157

The following is an explicit formula for D(m)n (x, y; a, b, c).

Theorem 2.9 For n,m ≥ 0, we have

D(m)n (x, y; a, b, c)

= 2∞∑

j=0

( j !)2(

n∑

l=0

∞∑

i=0

(−1)i(ln cxai+2bi+1

)n−l − (ln cxai+1bi

)n−l

(ln a + ln b)n−l

(n

l

){lj

})

×(

m∑

r=0

(y ln c + 2 ln a + ln b

ln a + ln b

)m−r (m

r

){rj

})

Proof Using Theorem 2.8,

∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m!

= 2e

(y ln c+ln aln a+ln b

)ue

(x ln c+ln aln a+ln b

)tet+u

(1 − e−t

)

(et + 1)(1 − (et − 1)(eu − 1))

= 2e

(y ln c+2 ln a+ln b

ln a+ln b

)ue

(x ln c+2 ln a+ln b

ln a+ln b

)t (1 − e−t)

∞∑

i=0

(−1)iei t∞∑

j=0

(et − 1) j (eu − 1) j

= 2e

(y ln c+2 ln a+ln b

ln a+ln b

)u

∞∑

i=0

(−1)ie

(x ln c+(i+2) ln a+(i+1) ln b

ln a+ln b

)t

∞∑

j=0

(et − 1) j (eu − 1) j

−2e

(y ln c+2 ln a+ln b

ln a+ln b

)u

∞∑

i=0

(−1)ie

(x ln c+(i+1) ln a+i ln b

ln a+ln b

)t

∞∑

j=0

(et − 1) j (eu − 1) j .

Applying the exponential generating function for

{nk

}in (15), we obtain

∞∑

n=0

∞∑

m=0

D(m)n (x, y; a, b, c)

tn

n!um

m!

= 2∞∑

j=0

⎜⎝ j !∞∑

i=0

(−1)i∞∑

n=0

(x ln c+(i+2) ln a+(i+1) ln b

ln a+ln b

)ntn

n!∞∑

m=0

{mj

}tm

m!

⎟⎠

×⎛

⎜⎝ j !∞∑

n=0

(y ln c+2 ln a+ln b

ln a+ln b

)nun

n!∞∑

m=0

{mj

}um

m!

⎟⎠

−2∞∑

j=0

⎜⎝ j !∞∑

i=0

(−1)i∞∑

n=0

(x ln c+(i+1) ln a+i ln b

ln a+ln b

)ntn

n!∞∑

m=0

{mj

}tm

m!

⎟⎠

Page 10: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

158 H. Jolany et al.

×⎛

⎜⎝ j !∞∑

n=0

(y ln c+2 ln a+ln b

ln a+ln b

)nun

n!∞∑

m=0

{mj

}um

m!

⎟⎠

= 2∞∑

j=0

(j !

∞∑

i=0

∞∑

l=0

l∑

m=0

(−1)i(x ln c+(i+2) ln a+(i+1) ln b

ln a+ln b

)l−m(l

m

) {mj

}t l

l!

)

×⎛

⎝ j !∞∑

p=0

p∑

r=0

(y ln c + 2 ln a + ln b

ln a + ln b

)p−r (p

r

) {rj

}u p

p!

−2∞∑

j=0

(j !

∞∑

i=0

∞∑

l=0

l∑

m=0

(−1)i(x ln c + (i + 1) ln a + i ln b

ln a + ln b

)l−m (l

m

) {mj

}t l

l!

)

×⎛

⎝ j !∞∑

p=0

p∑

r=0

(y ln c + 2 ln a + ln b

ln a + ln b

)p−r (p

r

) {rj

}u p

p!

=∞∑

n=0

∞∑

m=0

tn

n!um

m! 2∞∑

j=0

( j !)2(

n∑

l=0

∞∑

i=0

(−1)i(x ln c+(i+2) ln a+(i+1) ln b

ln a+ln b

)n−l

×(n

l

) {lj

}) (m∑

r=0

(y ln c + 2 ln a + ln b

ln a + ln b

)m−r (m

r

) {rj

})

−∞∑

n=0

∞∑

m=0

tn

n!um

m! 2∞∑

j=0

( j !)2(

n∑

l=0

∞∑

i=0

(−1)i(x ln c + (i + 1) ln a + i ln b

ln a + ln b

)n−l

×(n

l

) {lj

}) (m∑

r=0

(y ln c + 2 ln a + ln b

ln a + ln b

)m−r (m

r

) {rj

})

Comparing the coefficients yields the desired result. ��

3 Generalized multi-poly-Euler polynomials

Let us define a more general form of multi-poly-Euler polynomials.

Definition 3.1 The generalized multi-poly-Euler polynomials with parameters a, band c are defined by

2Li(k1,k2,...,kr )(1 − (ab)−t )

(a−t + bt )rcrxt =

∞∑

n=0

E (k1,k2,...,kr )n (x; a, b, c)

tn

n! . (22)

In particular,

E (k1,k2,...,kr )n (x) = E (k1,k2,...,kr )

n (x; 1, e, e)E (k1,k2,...,kr )n (a, b) = E (k1,k2,...,kr )

n (0; a, b)

Page 11: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 159

The following theorem contains some identities for E (k1,k2,...,kr )n (x; a, b, c) which

can be derived using the process in deriving the identities in Theorems 2.1–2.3.

Theorem 3.2 The generalized multi-poly-Euler polynomials satisfy the followingrelations

E (k1,k2,...,kr )n (x; a, b, c) =

n∑

i=0

(n

i

)(r ln c)n−i E (k1,k2,...,kr )

i (a, b)xn−i

E (k1,k2,...,kr )n (x; a, b, c) = (ln a + ln b)n E (k1,k2,...,kr )

n

(r x ln c + ln a

ln a + ln b

)

d

dxE (k1,k2,...,kr )n+1 (x; a, b, c) = (n + 1)(r ln c)E (k1,k2,...,kr )

n (x; a, b, c) (23)

The characterization of Appell polynomials is supposed to be used to estab-lish the addition formula for the generalized multi-poly-Euler polynomials using(23). But the constant r ln c that appeared in the expression of (23) disqualifiesE (k1,k2,...,kr )n (x; a, b, c) to be an Appell polynomial and to, consequently, satisfy

any of the conditions of the said characterization. However, we can derive theaddition formula using the same method in deriving the addition formula forE (k1,k2,...,kr )n (x; a, b) in [14]. The following theorem contains the addition formula

for E (k1,k2,...,kr )n (x; a, b, c).

Theorem 3.3 The generalized poly-Euler polynomials satisfy the following additionformula

E (k1,k2,...,kr )n (x + y; a, b, c) =

n∑

i=0

(n

i

)(r ln c)n−i E (k1,k2,...,kr )

i (x; a, b, c)yn−i .

Proof

∞∑

n=0

E (k1,k2,...,kr )n (x + y; a, b, c)

tn

n! = 2Li(k1,k2,...,kr )(1 − (ab)−t )

(a−t + bt )rc(x+y)r t

= 2Li(k1,k2,...,kr )(1 − (ab)−t )

(a−t + bt )rcxrt cyrt

=( ∞∑

n=0

E (k1,k2,...,kr )n (x; a, b, c)

tn

n!

)( ∞∑

n=0

(yr ln c)ntn

n!

)

=∞∑

n=0

(n∑

i=0

(n

i

)(yr ln c)n−i E (k1,k2,...,kr )

i (x; a, b, c)

)tn

n! .

Comparing the coefficients of tnn! yields the desired result. ��

The next theorem contains an explicit formula for E (k1,k2,...,kr )n (x; a, b, c).

Page 12: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

160 H. Jolany et al.

Theorem 3.4 The generalized multi-poly-Euler polynomials have the followingexplicit formula

E (k1,k2,...,kr )n (x; a, b, c)

=n∑

i=0

0≤m1≤m2≤···≤mrc1+c2+···=r

mr∑

j=0

2(r x ln c − j ln ab)n−i r !(−1) j+s(s ln ab+r ln a)i(mr

j

)(ni

)

(c1!c2! · · · )(mk11 mk2

2 · · ·mkrr )

,

(24)

where s = c1 + 2c2 + · · ·Proof From Definition 3.1, we have

Li(k1,k2,...,kr )(1 − (ab)−t )crxt =∑

0≤m1≤m2≤···≤mr

(1 − (ab)−t )mr

mk11 mk2

2 · · ·mkrr

er xt ln c

=∑

0≤m1≤m2≤···≤mr

1

mk11 mk2

2 · · ·mkrr

mr∑

j=0

(−1) j(mr

j

) ∞∑

n=0

(r x ln c − j ln ab)ntn

n!

=∞∑

n=0

⎝∑

0≤m1≤m2≤···≤mr

mr∑

j=0

(−1) j (r x ln c − j ln ab)n(mr

j

)

mk11 mk2

2 · · ·mkrr

⎠ tn

n! .

On the other hand,

(1

a−t + bt

)r

= art(

1

1 + (ab)t

)r

= art

⎝∑

n≥0

(−1)n(ab)nt

⎠r

=∑

c1+c2+···=r

r !(−1)c1+2c2+···

c1!c2! · · · et[r ln a+(c1+2c2+··· ) ln ab

=∑

c1+c2+···=r

r !(−1)c1+2c2+···

c1!c2! · · ·∞∑

n=0

(r ln a + (c1 + 2c2 + · · · ) ln ab)n tn

n!

=∞∑

n=0

(∑

c1+c2+···=r

r !(−1)c1+2c2+···(r ln a+(c1+2c2+· · · ) ln ab)nc1!c2! · · ·

)tn

n! .

Hence,

2Li(k1,k2,...,kr )(1 − (ab)−t )

(a−t + bt )rcrxt =2Li(k1,k2,...,kr )(1 − (ab)−t )er xt ln cart

(1

1+(ab)t

)r

= 2∞∑

n=0

n∑

i=0

⎝∑

0≤m1≤m2≤···≤mr

mr∑

j=0

(−1) j (r x ln c − j ln ab)n−i(mr

j

)

mk11 mk2

2 · · ·mkrr

⎠ tn−i

(n − i)!

Page 13: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

More properties on multi-poly-Euler polynomials 161

×(

c1+c2+···=r

r !(−1)c1+2c2+···(r ln a + (c1 + 2c2 + · · · ) ln ab)ic1!c2! · · ·

)t i

i !

= 2∞∑

n=0

n∑

i=0

0≤m1≤m2≤···≤mrc1+c2+···=r

mr∑

j=0

H(r, i, j, n, a, b)

(c1!c2! · · · )(mk11 mk2

2 · · ·mkrr )

tn

n!

where

H(r, i, j, n, a, b) = (r x ln c − j ln ab)n−i r !(−1) j+c1+2c2+···

×(r ln a + (c1 + 2c2 + · · · ) ln ab)i(mr

j

)(n

i

).

By comparing the coefficient of tn/n!, we obtain the desired explicit formula. ��

Remark 3.5 Identities parallel to those in Theorems 2.8 and 2.9 can possibly be estab-lished. However, the derivation is quite complicated that it may not be of interest tomany. Interested reader may try to obtain the said identities.

References

1. Araci, S., Acikgoz, M., Sen, E.: On the extended Kims p-adic q-deformed fermionic integrals in thep-adic integer ring. J. Number Theory 133(10), 3348–3361 (2013)

2. Bayad, A., Hamahota, Y.: Arakawa-Kaneko L-functions and generalized poly-Bernoulli polynomials.J. Number Theory 131, 1020–1036 (2011)

3. Bayad, A., Hamahota, Y.: Multiple polylogarithms and multi-poly-Bernoulli polynomials. Funct.Approx. Comment. Math. 46(1), 45–61 (2012)

4. Bayad, A., Hamahota, Y.: Polylogarithms and poly-Bernoulli polynomials. Kyushu J. Math. 65, 15–24(2011)

5. Benyi, B.: Advances in Bijective Combinatorics. Ph.D. Thesis, University of Szeged, Hungary (2014)6. Brewbaker, C.:A combinatorial interpretation of the poly-Bernoulli numbers and two fermat analogues.

Integers 8(1), #A02 (2008)7. Candelpergher, B., Coppo, M.A.: A new class of identities involving Cauchy numbers, harmonic

numbers and zeta values. Ramanujan J. 27(3), 305–328 (2012)8. Comtet, L.: Advanced Combinatorics. D. Reidel Publishing Company, Dordrecht (1974)9. Coppo, M.-A., Candelpergher, B.: The Arakawa-Kaneko zeta function. Ramanujan J. 22, 153–162

(2010)10. Hamahota, Y., Masubuchi, H.: Special multi-poly-Bernoulli numbers. J. Integer Seq. 10 (2007)11. Hamahata, Y.: Poly-Euler polynomials and Arakawa-Kaneko type zeta functions. Funct. Approx.

Comment. Math. 51(1), 7–22 (2014)12. Jolany, H., Alikelaye, R.E., Mohamad, S.S.: Some results on the generalization of Bernoulli, Euler and

Genocchi polynomials. Acta Univ. Apulensis Math. Inform. 27, 299–306 (2011)13. Jolany, H., Aliabadi, M., Corcino, R.B., Darafsheh, M.R.: A note on multi poly-Euler numbers and

Bernoulli polynomials. Gen. Math. 20(2–3), 122–134 (2012)14. Jolany, H., Darafsheh, M.R., Alikelaye, R.E.: Generalizations of poly-Bernoulli numbers and polyno-

mials. Int. J. Math. Comb. 2, 7–14 (2010)15. Kaneko, M.: Poly-Bernoulli numbers. J. Theor. Nr. Bordx. 9, 221–228 (1997)16. Lee, D.W.: On multiple Appell polynomials. Proc. Am. Math. Soc. 139(6), 2133–2141 (2011)17. Ohno, Y., Sasaki, Y.: On the parity of poly-Euler numbers. RIMS Kokyuroku Bessatsu B 32, 271–278

(2012)

Page 14: More properties on multi-poly-Euler polynomialshjolany/jolany-bernoulli.pdf · Roberto B. Corcino rcorcino@yahoo.com Takao Komatsu komatsu@whu.edu.cn 1 Laboratoire Paul Painlevé,

162 H. Jolany et al.

18. Shohat, J.: The relation of the classical orthogonal polynomials to the polynomials of Appell. Am. J.Math. 58, 453–464 (1936)

19. Toscano, L.: Polinomi Ortogonali o Reciproci di Ortogonali Nella classe di Appell. Lect. Mat. 11,168–174 (1956)