关于第三类退化的Poly-Cauchy多项式的组合恒等式
Some Identities on Degenerate Poly-Cauchy Polynomials of the Third Kind
摘要: 本文利用发生函数和Riordan阵研究了第三类退化的Poly-Cauchy多项式相关的恒等式。首先,运用发生函数方法给出第三类退化的Poly-Cauchy多项式的性质,从而得到了关于第三类退化的Poly-Cauchy多项式的一些组合恒等式。其次,应用Riordan阵法,建立了第三类退化的Poly-Cauchy多项式与两类Stirling数、Lab数、Bell数之间的一些关系式。
Abstract: In this paper, using generating functions and Riordan arrays, we establish some identities involving the degenerate Poly-Cauchy polynomials of the third kind. Using the generating functions, we explore some properties of the degenerate Poly-Cauchy polynomials of the third kind, and obtain some combinatorial identities involving the degenerate Poly-Cauchy polynomials of the third kind. In addition, using Riordan arrays, we give some interesting relations involving degenerate Poly-Cauchy polynomials of the third kind with the Stirling numbers of both kinds, the Lab numbers and the Bell numbers.
文章引用:道如娜图亚, 乌云高娃. 关于第三类退化的Poly-Cauchy多项式的组合恒等式[J]. 应用数学进展, 2022, 11(1): 492-502. https://doi.org/10.12677/AAM.2022.111057

1. 预备知识

在文献 [1] 中,Cauchy多项式 C n ( x ) 的发生函数定义为:

n 0 C n ( x ) t n n ! = t ln ( 1 + t ) ( 1 + t ) x . (1)

其中,当 x = 0 时,称 C n ( 0 ) = C n 为Cauchy数。

首先,我们引入第三类退化的Poly-Cauchy多项式的定义,其发生函数的定义为(文献 [2] ):

n 0 C n , λ , 3 ( x ) t n n ! = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ . (2)

其次,我们给出本文中用到的几种组合序列的发生函数的定义:即第一类Stirling数 s ( n , k ) ;第一类无符号Stirling数 | s ( n , k ) | ;第二类Stirling数 S ( n , k ) ;Lab数 L ( n , k ) ;第一类Bell数 B ( n , k ) 以及第二类Bell数 β ( n , k ) 的发生函数定义如下(文献 [3] ):

n k s ( n , k ) t n n ! = 1 k ! ln k ( 1 + t ) , (3)

n k | s ( n , k ) | t n n ! = 1 k ! ( ln 1 1 t ) k , (4)

n k S ( n , k ) t n n ! = 1 k ! ( e t 1 ) k , (5)

n k L ( n , k ) t n n ! = 1 k ! ( t 1 + t ) k , (6)

n k B ( n , k ) t n n ! = 1 k ! ( exp ( e t 1 ) 1 ) k , (7)

n k β ( n , k ) t n n ! = 1 k ! ln k ( 1 + ln ( 1 + t ) ) . (8)

下面引进一个引理:

引理1 令 D = ( g ( t ) , f ( t ) ) = { d n , k } n , k N 为一个Riordan阵,令 h ( t ) = k 0 h k t k 为序列 { h n } n N 的发生函数,则有(文献 [3] )

k = 0 n d n , k h k = [ t n ] g ( t ) h ( f ( t ) ) = [ t n ] g ( t ) h ( y ) ( y = f ( t ) ) . (9)

2. 第三类退化的Poly-Cauchy多项式与一些组合数间的关系

定理1 设n为非负整数,则有

C n , λ , 3 ( x + y ) = k = 0 n j = 0 k ( n k ) ( y λ ) j λ j s ( k , j ) C n k , λ , 3 ( x ) . (10)

证明:由第三类退化的Poly-Cauchy多项式的发生函数(2),可得

n 0 C n , λ , 3 ( x + y ) t n n ! = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x + y λ = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ ( 1 + λ ln ( 1 + t ) ) y λ = ( n 0 C n , λ , 3 ( x ) t n n ! ) ( j 0 ( y λ ) j λ j ln j ( 1 + t ) j ! ) = ( n 0 C n , λ , 3 ( x ) t n n ! ) ( j 0 ( y λ ) j λ j n j s ( n , j ) t n n ! ) = ( n 0 C n , λ , 3 ( x ) t n n ! ) ( n 0 j = 0 n ( y λ ) j λ j s ( n , j ) t n n ! ) = n 0 k = 0 n j = 0 k ( n k ) ( y λ ) j λ j s ( k , j ) C n k , λ , 3 ( x ) t n n !

比较等式两边 t n n ! 的系数,可完成定理的证明。

定理2 设n为非负整数,则有

C n , λ , 3 ( x + 1 ) + C n , λ , 3 ( x ) = k = 0 n j = 0 k ( k j ) ( 2 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) s ( n , k ) . (11)

证明:由式(2),可得

n 0 C n , λ , 3 ( x + 1 ) + C n , λ , 3 ( x ) t n n ! = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x + 1 λ + λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ + 1 ) = λ ( ( 1 + λ ln ( 1 + t ) ) 2 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ

= λ ( k 1 ( 2 λ ) k λ k ln k ( 1 + t ) k ! ) 1 ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ

= λ ( k 1 ( 2 λ ) k λ k ln k 1 ( 1 + t ) k ! ) λ ln ( 1 + t ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ = λ ( k 0 ( 2 λ ) k + 1 1 k + 1 λ k ln k ( 1 + t ) k ! ) ( k 0 C k ( x λ ) λ k ln k ( 1 + t ) k ! ) = λ k 0 j = 0 k ( k j ) ( 2 λ ) j + 1 λ k j + 1 C k l ( x λ ) ln k ( 1 + t ) k ! = k 0 j = 0 k ( k j ) ( 2 λ ) j + 1 λ k + 1 j + 1 C k l ( x λ ) n k s ( n , k ) t n n ! = n 0 k = 0 n j = 0 k ( k j ) s ( n , k ) ( 2 λ ) j + 1 λ k + 1 j + 1 C k l ( x λ ) t n n !

比较等式两边 t n n ! 的系数,可得定理的证明。

在定理2中,令 x = 0 ,可得如下推论。

推论2 设n为非负整数,则有

C n , λ , 3 ( 1 ) + C n , λ , 3 ( 0 ) = k = 0 n j = 0 k ( k j ) ( 2 λ ) j + 1 λ k + 1 j + 1 C k j s ( n , k ) . (12)

定理3 设n为非负整数,则有

C n , λ , 3 ( x 1 ) = k = 0 n j = 0 k ( k j ) ( 1 ) j 1 λ j + 1 λ k + 1 j + 1 C k j ( x λ ) s ( n , k ) . (13)

证明:由式(2),可得

n 0 C n , λ , 3 ( x 1 ) t n n ! = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x 1 λ = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ ( 1 + λ ln ( 1 + t ) ) 1 λ = λ ( 1 ( 1 + λ ln ( 1 + t ) ) 1 λ ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ = λ ( ( 1 + λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ = λ k 1 ( 1 λ ) k λ k ln k ( 1 + t ) k ! ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ

= λ k 0 ( 1 ) k + 1 1 λ k + 1 λ k ln k ( 1 + t ) ( k + 1 ) ! λ ln ( 1 + t ) ln ( 1 + λ ln ( 1 + t ) ) ( 1 + λ ln ( 1 + t ) ) x λ = ( λ k 0 ( 1 ) k + 1 1 λ k + 1 λ k k + 1 ln k ( 1 + t ) k ! ) ( k 0 λ k C k ( x λ ) ln k ( 1 + t ) k ! ) = λ k 0 j = 0 k ( k j ) ( 1 ) j + 1 1 λ j + 1 λ k j + 1 C k j ( x λ ) ln k ( 1 + t ) k ! = k 0 j = 0 k ( k j ) ( 1 ) j 1 λ j + 1 λ k + 1 j + 1 C k j ( x λ ) n k s ( n , k ) t n n ! = n 0 k = 0 n j = 0 k ( k j ) ( 1 ) j 1 λ j + 1 λ k + 1 j + 1 C k j ( x λ ) s ( n , k ) t n n !

比较等式两边 t n n ! 的系数,可以得到结论(13)。

在定理3中,令 x = 0 ,即可得如下推论。

推论3 设n为非负整数,则有

C n , λ , 3 ( 1 ) = k = 0 n j = 0 k ( k j ) ( 1 ) j 1 λ j + 1 λ k + 1 j + 1 C k j s ( n , k ) . (14)

定理4 设n为非负整数,则有

( 1 ) n C n , λ , 3 ( x ) = k = 0 n j = 0 k ( k j ) ( 1 ) k ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) | s ( n , k ) | . (15)

证明:由式(2),可得

n 0 ( 1 ) n C n , λ , 3 ( x ) t n n ! = λ ( ( 1 + λ ln ( 1 t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 t ) ) ( 1 + λ ln ( 1 t ) ) x λ = λ ( ( 1 λ ln ( 1 1 t ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 1 t ) ) ( 1 λ ln ( 1 1 t ) ) x λ = λ k 1 ( λ ) k ( 1 λ ) k 1 k ! ( ln ( 1 1 t ) ) k ln ( 1 λ ln ( 1 1 t ) ) ( 1 λ ln ( 1 1 t ) ) x λ = λ k 0 ( λ ) k ( 1 λ ) k + 1 1 ( k + 1 ) ! ( ln ( 1 1 t ) ) k λ ln ( 1 1 t ) ln ( 1 λ ln ( 1 1 t ) ) ( 1 λ ln ( 1 1 t ) ) x λ

= λ ( k 0 ( λ ) k ( 1 λ ) k + 1 1 ( k + 1 ) ! ( ln ( 1 1 t ) ) k ) ( k 0 ( λ ) k C k ( x λ ) 1 k ! ( ln ( 1 1 t ) ) k )

= λ k 0 j = 0 k ( k j ) ( λ ) k ( 1 λ ) j + 1 1 j + 1 C k j ( x λ ) 1 k ! ( ln ( 1 1 t ) ) k = λ k 0 j = 0 k ( k j ) ( λ ) k ( 1 λ ) j + 1 1 j + 1 C k j ( x λ ) n k | s ( n , k ) | t n n ! = n 0 k = 0 n j = 0 k ( k j ) ( 1 ) k ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) | s ( n , k ) | t n n !

比较等式两边 t n n ! 的系数,可完成定理的证明。

定理5 设n为非负整数,则有

k = 0 n S ( n , k ) C k , λ , 3 ( x ) = k = 0 n ( n k ) ( 1 λ ) k + 1 λ n + 1 k + 1 C n k ( x λ ) . (16)

证明:因为 { k ! n ! S ( n , k ) } = ( 1 , e t 1 ) ,再由引理1和式(2),则有

k = 0 n S ( n , k ) C k , λ , 3 ( x ) = n ! k = 0 n k ! n ! S ( n , k ) C k , λ , 3 ( x ) k ! = n ! [ t n ] λ ( ( 1 + λ ln ( 1 + y ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + y ) ) ( 1 + λ ln ( 1 + y ) ) x z λ ( y = e t 1 ) = n ! [ t n ] λ ( ( 1 + λ t ) 1 λ 1 ) ln ( 1 + λ t ) ( 1 + λ t ) x z λ = n ! [ t n ] n 1 ( 1 λ ) n ( λ t ) n n ! λ ln ( 1 + λ t ) ( 1 + λ t ) x z λ

= n ! [ t n ] n 0 ( 1 λ ) n + 1 λ n + 1 t n ( n + 1 ) ! λ t ln ( 1 + λ t ) ( 1 + λ t ) x z λ = n ! [ t n ] ( n 0 ( 1 λ ) n + 1 λ n + 1 n + 1 t n n ! ) ( n 0 λ n C n ( x λ ) t n n ! ) = n ! [ t n ] n 0 k = 0 n ( n k ) ( 1 λ ) k + 1 λ n + 1 k + 1 C n k ( x λ ) t n n ! = k = 0 n ( n k ) ( 1 λ ) k + 1 λ n + 1 k + 1 C n k ( x λ )

下面引进序列 { f n } n N { g n } n N 的反演公式

f n = k = 0 n S ( n , k ) g k g n = k = 0 n s ( n , k ) f k . (17)

由式(17)和定理5立即可得如下等式。

定理6 设n为非负整数,则有

k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) s ( n , k ) = C n , λ , 3 ( x ) . (18)

定理7 设n为非负整数,则有

k = 0 n j = 0 k λ k S ( n , k ) S ( k , j ) C j , λ , 3 ( x ) = λ ( n 1 ) ( x + 1 ) n + 1 x n + 1 n + 1 . (19)

证明:由定理5的证明可知

k = 0 n S ( n , k ) C k , λ , 3 ( x ) = λ ( ( 1 + λ t ) 1 λ 1 ) ln ( 1 + λ t ) ( 1 + λ t ) x λ . (20)

因为 { k ! n ! S ( n , k ) } = ( 1 , e t 1 ) ,再由式(9)和式(20),可得

k = 0 n j = 0 k λ k S ( n , k ) S ( k , j ) C j , λ , 3 ( x ) = n ! k = 0 n k ! n ! λ k S ( n , k ) j = 0 k S ( k , j ) C j , λ , 3 ( x ) k ! = n ! [ t n ] λ ( ( 1 + λ y ) 1 λ 1 ) ln ( 1 + λ y ) ( 1 + λ y ) x λ ( y = e t 1 λ ) = n ! [ t n ] λ ( ( 1 + λ e t 1 λ ) 1 λ 1 ) ln ( 1 + λ e t 1 λ ) ( 1 + λ e t 1 λ ) x λ = n ! [ t n ] λ ( e t λ 1 ) t e x t λ = n ! [ t n + 1 ] λ ( e t λ 1 ) e x t λ = λ ( n 1 ) ( x + 1 ) n + 1 x n + 1 n + 1

由式(17)和定理7立即可得如下结论。

定理8 设n为非负整数,则有

k = 0 n j = 0 k λ n + k + 1 ( x + 1 ) n + 1 x n + 1 n + 1 s ( n , k ) s ( k , j ) = C n , λ , 3 ( x ) .(21)

定理9 设n为非负整数,则有

k = 0 n j = 0 k S ( n , k ) L ( k , j ) C j , λ , 3 ( x ) = k = 0 n ( n k ) ( 1 λ ) k + 1 ( 1 ) n λ n + 1 k + 1 C n k ( x λ ) .(22)

证明:因为 { k ! n ! L ( n , k ) } = ( 1 , t 1 + t ) ,再由式(9)和式(2),可得

k = 0 n L ( n , k ) C k , λ , 3 ( x ) = n ! [ t n ] λ ( ( 1 λ ln ( 1 + t ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 + t ) ) ( 1 λ ln ( 1 + t ) ) x λ , (23)

又由式(5),可得

k = 0 n j = 0 k S ( n , k ) L ( k , j ) C j , λ , 3 ( x ) = n ! k = 0 n k ! n ! j = 0 k L ( k , j ) C j , λ , 3 ( x ) k ! S ( n , k ) = n ! [ t n ] λ ( ( 1 λ ln ( 1 + y ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 + y ) ) ( 1 λ ln ( 1 + y ) ) x z λ ( y = e t 1 ) = n ! [ t n ] λ ( ( 1 λ ln ( 1 + e t 1 ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 + e t 1 ) ) ( 1 λ ln ( 1 + e t 1 ) ) x z λ = n ! [ t n ] λ ( ( 1 λ t ) 1 λ 1 ) ln ( 1 λ t ) ( 1 λ t ) x z λ

= n ! [ t n ] n 1 ( 1 λ ) n ( λ t ) n n ! λ ln ( 1 λ t ) ( 1 λ t ) x z λ = n ! [ t n ] n 0 ( 1 λ ) n + 1 λ n + 1 ( t ) n ( n + 1 ) ! λ t ln ( 1 λ t ) ( 1 λ t ) x z λ = n ! [ t n ] ( n 0 ( 1 ) n ( 1 λ ) n + 1 λ n + 1 n + 1 t n n ! ) ( n 0 ( λ ) n C n ( x λ ) t n n ! ) = n ! [ t n ] ( 1 λ ) k + 1 ( 1 ) n λ n + 1 k + 1 C n k ( x λ ) t n n ! = k = 0 n ( n k ) ( 1 λ ) k + 1 ( 1 ) n λ n + 1 k + 1 C n k ( x λ )

由式(17)和定理9,可得如下结论。

定理10 设n为非负整数,则有

k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 ( λ ) k + 1 j + 1 C k j ( x λ ) s ( n , k ) = k = 0 n L ( n , k ) C k , λ , 3 ( x ) . (24)

定理11 设n为非负整数,则有

k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) | s ( n , k ) | = k = 0 n j = 0 k | s ( n , k ) | S ( k , j ) C j , λ , 3 ( x ) = k = 0 n ( 1 ) n L ( n , k ) C k , λ , 3 ( x ) (25)

证明:由式(6)有

n k L ( n , k ) ( t ) n n ! = 1 k ! ( t 1 t ) k , (26)

再由式(9)有

k = 0 n ( 1 ) n L ( n , k ) C k , λ , 3 ( x ) = n ! [ t n ] λ ( ( 1 λ ln ( 1 t ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 t ) ) ( 1 λ ln ( 1 t ) ) x λ = n ! [ t n ] λ ( ( 1 + λ ln ( 1 1 t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 1 t ) ) ( 1 + λ ln ( 1 1 t ) ) x λ = n ! [ t n ] λ k 1 λ k ( 1 λ ) k 1 k ! ( ln ( 1 1 t ) ) k ln ( 1 + λ ln ( 1 1 t ) ) ( 1 + λ ln ( 1 1 t ) ) x λ = n ! [ t n ] λ k 0 λ k ( 1 λ ) k + 1 1 ( k + 1 ) ! ( ln ( 1 1 t ) ) k λ ln ( 1 1 t ) ln ( 1 + λ ln ( 1 1 t ) ) ( 1 + λ ln ( 1 1 t ) ) x λ

= n ! [ t n ] λ ( k 0 λ k ( 1 λ ) k + 1 1 ( k + 1 ) ! ( ln ( 1 1 t ) ) k ) ( k 0 λ k C k ( x λ ) 1 k ! ( ln ( 1 1 t ) ) k ) = n ! [ t n ] λ k 0 j = 0 k ( k j ) λ k ( 1 λ ) j + 1 1 j + 1 C k j ( x λ ) 1 k ! ( ln ( 1 1 t ) ) k = n ! [ t n ] λ k 0 j = 0 k ( k j ) λ k ( 1 λ ) j + 1 1 j + 1 C k j ( x λ ) n k | s ( n , k ) | t n n ! = k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) | s ( n , k ) |

而由式(14)和式(9),还可以得到

k = 0 n j = 0 k | s ( n , k ) | S ( k , j ) C j , λ , 3 ( x ) = n ! k = 0 n k ! n ! | s ( n , k ) | j = 0 k S ( k , j ) C j , λ , 3 ( x ) k ! = n ! [ t n ] λ ( ( 1 + λ y ) 1 λ 1 ) ln ( 1 + λ y ) ( 1 + λ y ) x λ ( y = ln ( 1 1 t ) ) = n ! [ t n ] λ ( ( 1 + λ ln ( 1 1 t ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 1 t ) ) ( 1 + λ ln ( 1 1 t ) ) x λ = n ! [ t n ] λ ( ( 1 λ ln ( 1 t ) ) 1 λ 1 ) ln ( 1 λ ln ( 1 t ) ) ( 1 λ ln ( 1 t ) ) x λ = k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) | s ( n , k ) |

定理12 设n为非负整数,则有

k = 0 n j = 0 k ( k j ) S ( n , k ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) = k = 0 n B ( n , k ) C k , λ , 3 ( x ) . (27)

证明:因为 { k ! n ! B ( n , k ) } = ( 1 , exp ( e t 1 ) 1 ) ,再由式(9)和式(2),可得

k = 0 n B ( n , k ) C k , λ , 3 ( x ) = n ! k = 0 n k ! n ! B ( n , k ) C k , λ , 3 ( x ) k ! = n ! [ t n ] λ ( ( 1 + λ ln ( 1 + y ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + y ) ) ( 1 + λ ln ( 1 + y ) ) x λ ( y = exp ( e t 1 ) 1 ) = n ! [ t n ] λ ( ( 1 + λ ln ( 1 + exp ( e t 1 ) 1 ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + exp ( e t 1 ) 1 ) ) ( 1 + λ ln ( 1 + exp ( e t 1 ) 1 ) ) x λ = n ! [ t n ] λ ( ( 1 + λ ( e t 1 ) ) 1 λ 1 ) ln ( 1 + λ ( e t 1 ) ) ( 1 + λ ( e t 1 ) ) x λ

= n ! [ t n ] λ k 1 ( 1 λ ) k λ k ( e t 1 ) k k ! 1 ln ( 1 + λ ( e t 1 ) ) ( 1 + λ ( e t 1 ) ) x λ = n ! [ t n ] λ k 1 ( 1 λ ) k λ k ( e t 1 ) k 1 k ! λ ( e t 1 ) ln ( 1 + λ ( e t 1 ) ) ( 1 + λ ( e t 1 ) ) x λ = n ! [ t n ] λ ( k 0 ( 1 λ ) k + 1 λ k ( e t 1 ) k 1 ( k + 1 ) ! ) ( k 0 C k ( x λ ) λ k ( e t 1 ) k k ! ) = n ! [ t n ] k 0 j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) ( e t 1 ) k k !

= n ! [ t n ] k 0 j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) n k S ( n , k ) t n n ! = n ! [ t n ] n 0 k = 0 n j = 0 k ( k j ) S ( n , k ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) t n n ! = k = 0 n j = 0 k ( k j ) S ( n , k ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ )

定理13 设n为非负整数,则有

k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) β ( n , k ) = k = 0 n C k , λ , 3 ( x ) s ( n , k ) . (28)

证明:由第三类退化的Poly-Cauchy多项式的发生函数(2)有

k 0 C k , λ , 3 ( x ) ln k ( 1 + t ) k ! = k 0 C k , λ , 3 ( x ) n k s ( n , k ) t n n ! = n 0 k = 0 n C k , λ , 3 ( x ) s ( n , k ) t n n ! = λ ( ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) 1 λ 1 ) ln ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) x λ = λ k 1 ( 1 λ ) k λ k ln k ( 1 + ln ( 1 + t ) ) k ! 1 ln ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) x λ = λ k 0 ( 1 λ ) k + 1 1 k + 1 λ k ln k ( 1 + ln ( 1 + t ) ) k ! λ ln ( 1 + ln ( 1 + t ) ) ln ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) ( 1 + λ ln ( 1 + ln ( 1 + t ) ) ) x λ

= λ ( k 0 ( 1 λ ) k + 1 λ k k + 1 ln k ( 1 + ln ( 1 + t ) ) k ! ) ( k 0 C k ( x λ ) λ k ln k ( 1 + ln ( 1 + t ) ) k ! ) = k 0 j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) ln k ( 1 + ln ( 1 + t ) ) k ! = k 0 j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) β ( n , k ) t n n ! = n 0 k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) β ( n , k ) t n n ! = k = 0 n j = 0 k ( k j ) ( 1 λ ) j + 1 λ k + 1 j + 1 C k j ( x λ ) β ( n , k )

比较等式两边 t n n ! 的系数,可完成定理的证明。

由式(17)和定理13,立即可得如下结论。

定理14 设n为非负整数,则有

k = 0 n j = 0 k i = 0 j ( j i ) ( 1 λ ) i + 1 λ j + 1 i + 1 C j i ( x λ ) β ( k , j ) S ( n , k ) = C n , λ , 3 ( x ) . (29)

基金项目

国家自然科学基金项目(11461050),内蒙古自然科学基金项目(2020MS01020)。

参考文献

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