OFFSET
0,3
COMMENTS
a(n) is the n-th term of the inverse Lah transform of the n-th powers.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..250
N. J. A. Sloane, Transforms
FORMULA
a(n) = n! * [x^n] Sum_{k>=0} k^n*(x/(1 + x))^k/k!.
MAPLE
A317278:= n-> `if`(n=0, 1, add((-1)^(n+j)*binomial(n-1, j-1)*binomial(n, j)*(n-j)!*j^n, j=0..n));
seq(A317278(n), n=0..30); # G. C. Greubel, Mar 09 2021
MATHEMATICA
Join[{1}, Table[Sum[(-1)^(n-k) Binomial[n-1, k-1] k^n n!/k!, {k, n}], {n, 18}]]
Join[{1}, Table[n! SeriesCoefficient[Sum[k^n (x/(1 + x))^k/k!, {k, n}], {x, 0, n}], {n, 18}]]
PROG
(Sage) [1]+[sum((-1)^(n+j)*binomial(n-1, j-1)*binomial(n, j)*factorial(n-j)*j^n for j in (0..n)) for n in (1..30)] # G. C. Greubel, Mar 09 2021
(Magma) [1]cat[(&+[(-1)^(n+j)*Binomial(n-1, j-1)*Binomial(n, j)*Factorial(n-j)*j^n: j in [0..n]]): n in [1..30]]; // G. C. Greubel, Mar 09 2021
(PARI) a(n) = if (n==0, 1, sum(k=0, n, (-1)^(n-k)*binomial(n-1, k-1)*k^n*n!/k!)); \\ Michel Marcus, Mar 10 2021; corrected Jun 13 2022
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Jul 25 2018
STATUS
approved