A371913 G.f. A(x) satisfies A(x) = 1 - x/A(x)^4 * (1 - A(x) - A(x)^5).

1, 1, 2, 0, -6, 12, 67, -152, -740, 2296, 9017, -35979, -113936, 579516, 1454975, -9493390, -18317155, 157178640, 220172289, -2618995381, -2377680689, 43783556265, 19149194005, -732638868460, 16196837316, 12246524817736, -5891297294673

Offset

0,3

Links

Table of n, a(n) for n=0..26.

Formula

a(n) = (1/n) * Sum_{k=0..n} binomial(n,k) * binomial(n-5*k,n-k-1) for n > 0.

Prog

(PARI) a(n) = if(n==0, 1, sum(k=0, n, binomial(n, k)*binomial(n-5*k, n-k-1))/n);

Crossrefs

Cf. A349332, A367725, A371914, A371915.

Cf. A371889, A371890.

Sequence in context: A110667 A347929 A129877 * A307581 A261566 A247443

Adjacent sequences: A371910 A371911 A371912 * A371914 A371915 A371916

Keyword

sign

Author

Seiichi Manyama, Apr 12 2024

Status

approved