A274716 - OEIS

A274716

a(2*n+1) = a(2*floor(n/2)+1) + n, a(2*n) = a(n), for n>=1 with a(1)=0.

0, 0, 1, 0, 3, 1, 4, 0, 7, 3, 8, 1, 10, 4, 11, 0, 15, 7, 16, 3, 18, 8, 19, 1, 22, 10, 23, 4, 25, 11, 26, 0, 31, 15, 32, 7, 34, 16, 35, 3, 38, 18, 39, 8, 41, 19, 42, 1, 46, 22, 47, 10, 49, 23, 50, 4, 53, 25, 54, 11, 56, 26, 57, 0, 63, 31, 64, 15, 66, 32, 67, 7, 70, 34, 71, 16, 73, 35, 74, 3, 78, 38, 79, 18, 81, 39, 82, 8, 85, 41, 86, 19, 88, 42, 89, 1, 94, 46, 95, 22, 97, 47, 98, 10, 101, 49, 102, 23, 104, 50, 105, 4, 109, 53, 110, 25, 112, 54, 113, 11, 116, 56, 117, 26, 119, 57, 120, 0

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OFFSET

1,5

COMMENTS

The values {2^a(n)} form the denominators of the coefficients in the g.f. of A274717, which satisfies G(x) = G(x^2) + sqrt( G(x^2) ).

LINKS

Table of n, a(n) for n=1..128.

FORMULA

a(2^n) = 0 for n>=0.

a(2*n-1) = A005187(n-1) for n>=1.

PROG

(PARI) {a(n) = if(n==1, 0, if(n%2==0, a(n/2), a(2*(n\4)+1) + n\2 ) )}