A107957 Partial sums of A107947.

1, 3, 6, 11, 17, 25, 36, 52, 69, 88, 110, 137, 170, 211, 263, 331, 400, 471, 545, 624, 709, 802, 906, 1026, 1163, 1319, 1497, 1702, 1940, 2219, 2550, 2949, 3349, 3751, 4156, 4566, 4982, 5406, 5841, 6292, 6760, 7247, 7756, 8292, 8861, 9471, 10133, 10863

Offset

0,2

Comments

Terms at positions 2^k is found in A107958.

Links

Table of n, a(n) for n=0..47.

Formula

a(n) = A107947(2^m + n) - A107947(2^m) when n <= 2^(m-1).

Example

a(3) = 6 = 22 - 16 = A107947(2^3 + 3) - A107947(2^3).
a(5) = 17 = 85 - 68 = A107947(2^4 + 5) - A107947(2^4).
a(8) = 52 = 120 - 68 = A107947(2^4 + 8) - A107947(2^4).

Prog

(PARI) {a(n)=local(A=[1, 2]); for(i=1, #binary(n), B=vector(#A, k, polcoeff(Ser(A)/(1-x), k-1)+A[2^#binary(#A-1)]); A=concat(A, B); ); sum(k=1, n, A[k])}

Crossrefs

Cf. A107946, A107947, A107948, A107958.

Sequence in context: A119639 A281376 A247586 * A000603 A003453 A011901

Adjacent sequences: A107954 A107955 A107956 * A107958 A107959 A107960

Keyword

nonn

Author

Paul D. Hanna, May 29 2005

Status

approved