A113148 Row 7 of table A113143; equal to INVERT of 7-fold factorials shifted one place right.

1, 1, 2, 11, 141, 2928, 82597, 2925973, 124502114, 6179425823, 350316271761, 22326710345256, 1579953165170881, 122905129550802985, 10423661531476766834, 957176457621821573987, 94608465923392572536421

Offset

0,3

Links

Table of n, a(n) for n=0..16.

Formula

a(n) = Sum_{j=0..k} 7^(k-j)*A111146(k, j).

a(0) = 1; a(n+1) = Sum_{k=0..n} a(k)*A045754(n-k).

Example

A(x) = 1 + x + 2*x^2 + 11*x^3 + 141*x^4 + 2928*x^5 +...
= 1/(1 - x - x^2 - 8*x^3 - 120*x^4 -...- A045754(n)*x^(n+1)
-...).

Prog

(PARI) {a(n)=local(x=X+X*O(X^n)); A=1/(1-x-x^2*sum(j=0, n, x^j*prod(i=0, j, 7*i+1))); return(polcoeff(A, n, X))}

Crossrefs

Cf. A113143, A045754 (7-fold factorials).

Sequence in context: A295811 A177753 A183609 * A193209 A268743 A348797

Adjacent sequences: A113145 A113146 A113147 * A113149 A113150 A113151

Keyword

nonn

Author

Philippe Deléham and Paul D. Hanna, Oct 28 2005

Status

approved