A370731 a(n) is the least k >= 0 such that F(k) AND n = n (where F(k) denotes A000045(k), the k-th Fibonacci number and AND denotes the bitwise AND operator).

0, 1, 3, 4, 5, 5, 10, 10, 6, 7, 16, 16, 7, 7, 22, 22, 8, 8, 10, 10, 8, 8, 10, 10, 11, 11, 16, 16, 17, 17, 46, 46, 9, 10, 9, 10, 10, 10, 10, 10, 13, 13, 22, 22, 17, 17, 22, 22, 10, 10, 10, 10, 10, 10, 10, 10, 14, 14, 64, 64, 17, 17, 94, 94, 11, 11, 15, 16, 19

Offset

0,3

Comments

This sequence is well defined (see Comments in A370730).

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

Formula

a(A000045(k)) = k for any k != 2.

Mathematica

A370731[n_] := Block[{k = -1}, While[BitAnd[Fibonacci[++k], n] != n]; k];
Array[A370731, 100, 0] (* Paolo Xausa, Mar 01 2024 *)

Prog

(PARI) a(n) = { for (k = 0, oo, if (bitand(fibonacci(k), n)==n, return (k); ); ); }

Crossrefs

Cf. A000045, A370730.

Sequence in context: A278168 A130271 A139369 * A151555 A263728 A370760

Adjacent sequences: A370728 A370729 A370730 * A370732 A370733 A370734

Keyword

nonn,base

Author

Rémy Sigrist, Feb 28 2024

Status

approved