A072648 a(n) = [log_{Phi}(n*sqrt(5))], where log_{Phi} is logarithm in the base Phi ( = (sqrt(5)+1)/2) and [] stands for the floor function.

1, 3, 3, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10

Offset: 1

Author

Antti Karttunen, Jun 02 2002

Keywords

• nonn

Comments

An approximate "inverse" of A000045 (of the Fibonacci numbers).

Crossrefs

Used to construct A072649.

Programs

Maple

[seq(floor(log[(sqrt(5)+1)/2](n*sqrt(5))),n=1..120)];