A115568 Maximal Fibonacci exponent in prime factorization of n, or 1 if there is no Fibonacci exponent.

1, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 3, 2, 1, 3, 2, 1, 1, 1, 5, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 2, 2, 1, 1, 1, 2, 2, 1, 2, 1, 3, 1, 3, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 5, 1, 2, 2, 2

Offset

1,4

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Index entries for sequences computed from exponents in factorization of n

Mathematica

Module[{fibs=Fibonacci[Range[10]]}, Table[Max[Select[FactorInteger[n][[All, 2]], MemberQ[fibs, #]&]]/.(-\[Infinity]->1), {n, 100}]] (* Harvey P. Dale, Apr 08 2022 *)

Prog

(PARI)
A010056(n) = { my(k=n^2); k+=(k+1)<<2; issquare(k) || (n>0 && issquare(k-8)); } \\ This function from Charles R Greathouse IV, Jul 30 2012
A115568(n) = { my(exps=factorint(n)[, 2], expswith1 = vector(1+length(exps), i, if(1==i, i, exps[i-1]))); vecmax(apply(e -> (A010056(e)*e), expswith1)); }; \\ Antti Karttunen, Jul 23 2017

Crossrefs

Cf. A000045, A010056, A122895.

Sequence in context: A096591 A316074 A332954 * A072909 A360721 A365552

Adjacent sequences: A115565 A115566 A115567 * A115569 A115570 A115571

Keyword

easy,nonn

Author

Giovanni Teofilatto, Mar 11 2006; revised Mar 13 2006

Extensions

Corrected by R. J. Mathar, Apr 03 2012

Status

approved