A160230 a(n) = A004760(n+1)-A160217(n), n>=1.

0, 0, 0, 3, 2, 0, 0, 6, 6, 4, 4, 3, 2, 0, 0, 15, 14, 12, 12, 11, 10, 8, 8, 6, 6, 4, 4, 3, 2, 0, 0, 30, 30, 28, 28, 27, 26, 24, 24, 22, 22, 20, 20, 19, 18, 16, 16, 15, 14, 12, 12, 11, 10, 8, 8, 6, 6, 4, 4, 3, 2, 0, 0, 63, 62, 60, 60, 59, 58, 56, 56, 54, 54, 52, 52, 51, 50

Offset

1,4

Links

Table of n, a(n) for n=1..77.

Formula

a(1)=0; a(2n)=a(2n+1)=2a(n) if A007814(n) is even, a(2n)=a(2n+1)+1=2a(n)+3 if A007814(n) is odd.

Example

a(2)=2a(1)=0; a(3)=2a(1)=0; a(4)=2a(2)+3=3; a(5)=2a(2)+2=2.

Prog

(PARI) is0(n)= (n<2) || binary(n)[2]; \\ A004760
list0(nn) = select(x->is0(x), vector(nn, k, k));
list7(nn) = {my(va = vector(nn)); va[1] = 3; for (n=2, nn, va[n]= nexta(va[n-1], n); ); va; } \\ A160217
listd(nn) = {my(v7 = list7(nn), v0 = list0(nn)); vector(min(#v0-1, #v7), k, v0[k+1] - v7[k]); } \\ Michel Marcus, Dec 15 2018

Crossrefs

Cf. A004760, A160217, A007814.

Sequence in context: A131370 A261180 A062707 * A293500 A240659 A246159

Adjacent sequences: A160227 A160228 A160229 * A160231 A160232 A160233

Keyword

nonn

Author

Vladimir Shevelev, May 04 2009

Extensions

Edited by N. J. A. Sloane, May 08 2009

More terms from Michel Marcus, Dec 15 2018

Status

approved