A152560 a(n) = A131205(A005578(n)).

1, 1, 3, 7, 37, 225, 2707, 47991, 1566965, 85002865, 8346008131, 1441358958439, 452666387604933, 257384373709193473, 268828878795481175283, 516988085848458847554135, 1844678455777198460320221077

Offset

0,3

Comments

Related to binary partitions (A000123); A131205 is defined by a(n) = a(n-1) + a(floor(n/2)) + a(ceiling(n/2)) and A005578(n) = (2^(n+1)+3+(-1)^n)/6.

Links

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

Prog

(PARI) {a(n)=local(N=(2^(n+1)+3+(-1)^n)/6, X=x+O(x^N)); polcoeff(1/((1-X)^2*prod(m=0, n-1, 1-X^(2^m))), N-1)}

Crossrefs

Cf. A131205, A005578, A000123.

Sequence in context: A208809 A086031 A174734 * A162926 A042895 A173561

Adjacent sequences: A152557 A152558 A152559 * A152561 A152562 A152563

Keyword

nonn

Author

Paul D. Hanna, Dec 22 2008

Status

approved