A081111 Let s(x)=floor(phi*x) where phi is the golden ratio (1+sqrt(5))/2; sequence gives the least k such that n divides s^k(n) where s^k(x) denotes s(s(s..s(x))..) k times, or 0 if no such number exists.

1, 2, 2, 6, 4, 6, 16, 4, 5, 3, 10, 3, 6, 3, 6, 3, 6, 8, 6, 13, 6, 20, 14, 24, 7, 16, 58, 26, 14, 16, 30, 33, 40, 8, 49, 18, 49, 18, 40, 37, 8, 32, 28, 24, 33, 18, 32, 8, 27, 61, 64, 22, 65, 30, 8, 36, 72, 14, 58, 51, 23, 30, 16, 11, 41, 10, 9, 30, 30, 32, 37, 16, 35, 59, 83, 18, 70, 64, 64

Offset

1,2

Links

Table of n, a(n) for n=1..79.

Example

s(4)=6, s(s(4))=9, s(s(s(4)))=14, s(s(s(s(4))))=22, s(s(s(s(s(4)))))=35, s(s(s(s(s(s(4))))))=56 and 56=s^6(4) is divisible by 4. Hence a(4)=6.

Crossrefs

Sequence in context: A077080 A273012 A222404 * A092686 A249796 A182411

Adjacent sequences: A081108 A081109 A081110 * A081112 A081113 A081114

Keyword

nonn

Author

Benoit Cloitre, Apr 15 2003

Status

approved