A113284 Odd bisection of A113281: a(n) = A113281(2*n+1).

1, 5, 23, 113, 579, 3047, 16319, 88489, 484255, 2668951, 14793169, 82372723, 460436551, 2582033519, 14519686915, 81845419777, 462319557311, 2616334071987, 14830559353869, 84189874112659, 478559722392493

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Formula

G.f.: ( (1+x)/(1-x)/(1-6*x+x^2)*(1-x-(1-6*x+x^2)^(1/2))/2/x )^(1/2).

a(n) ~ (1 + sqrt(2))^(2*n + 3/2) / (2*sqrt(Pi*n)). - Vaclav Kotesovec, Oct 18 2020

Prog

(PARI) {a(n)=local(x=X+X*O(X^n)); polcoeff( (2*(1+x)/(1-x)/(1-6*x+x^2)/(1-x+(1-6*x+x^2)^(1/2)) )^(1/2), n, X)}

Crossrefs

Cf. A113281, A113282, A113283.

Sequence in context: A199312 A320326 A299589 * A104090 A355055 A358607

Adjacent sequences: A113281 A113282 A113283 * A113285 A113286 A113287

Keyword

nonn

Author

Paul D. Hanna, Oct 22 2005

Status

approved