A171779 E.g.f.: A(x) = 1 + Sum_{n>=1} (1/n!)*Product_{k=1..n} -log(1 - k(k+1)x/2).

1, 1, 4, 38, 693, 21294, 1011792, 69920766, 6710698740, 862907887944, 144436271624388, 30735209866458888, 8152133649148990080, 2650418681465362135392, 1041182371767985227729504

Offset

0,3

Links

Table of n, a(n) for n=0..14.

Example

E.g.f.: A(x) = 1 + x + 4x^2/2! + 38x^3/3! + 693x^4/4! + 21294x^5/5! +...
A(x) = 1 - log(1-x) + log(1-x)*log(1-3x)/2! - log(1-x)*log(1-3x)*log(1-6x)/3! +...

Prog

(PARI) {a(n)=n!*polcoeff(1+sum(j=1, n, (1/j!)*prod(k=1, j, -log(1-k*(k+1)/2*x +x*O(x^n)))), n)}

Crossrefs

Cf. A135751, A171778.

Sequence in context: A177382 A201861 A379935 * A171203 A096332 A084284

Adjacent sequences: A171776 A171777 A171778 * A171780 A171781 A171782

Keyword

nonn

Author

Paul D. Hanna, Dec 18 2009

Status

approved