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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. 0
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 5 09:45 EST 2021. Contains 349543 sequences. (Running on oeis4.)