A377682 Expansion of e.g.f. (1 - x * log(1 - x))^2.

1, 0, 4, 6, 40, 180, 948, 5880, 42208, 344736, 3158640, 32091840, 358107264, 4353972480, 57290002560, 811116633600, 12295029657600, 198666240675840, 3408788192947200, 61898371424870400, 1185883197069312000, 23905764186329088000, 505813884019270041600

Offset: 0

Author

Seiichi Manyama, Nov 04 2024

Keywords

• nonn
• easy

Crossrefs

Cf. A377683, A377684.

Cf. A377685.

Programs

PARI

a(n) = n!*sum(k=0, n\2, k!*binomial(2, k)*abs(stirling(n-k, k, 1))/(n-k)!);

Formula

a(n) = n! * Sum_{k=0..floor(n/2)} k! * binomial(2,k) * |Stirling1(n-k,k)|/(n-k)!.