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A160685
Numbers k >= 1 such that A000005(A000045(k))/A000005(k) is an integer.
1
1, 3, 5, 6, 7, 8, 10, 11, 13, 14, 15, 17, 19, 21, 22, 23, 24, 25, 26, 27, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 46, 47, 50, 51, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 65, 66, 67, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79, 82, 83, 84, 85, 86, 87, 88, 89, 91, 93, 94
OFFSET
1,2
COMMENTS
A080651 is a subsequence. - R. J. Mathar, May 25 2009
LINKS
FORMULA
{n: A000005(n) | A063375(n)}. - R. J. Mathar, May 25 2009
MAPLE
A000045 := proc(n) combinat[fibonacci](n) ; end: A000005 := proc(n) numtheory[tau](n) ; end: A063375 := proc(n) A000005(A000045(n)) ; end: for n from 1 to 130 do if A063375(n) mod A000005(n) = 0 then printf("%d, ", n) ; fi; od: # R. J. Mathar, May 25 2009
MATHEMATICA
okQ[n_] := With[{tau = DivisorSigma[0, #]&},
IntegerQ[tau[Fibonacci[n]]/tau[n]]];
Select[Range[100], okQ] (* Jean-François Alcover, May 17 2023 *)
CROSSREFS
Sequence in context: A163162 A181744 A343217 * A080218 A080651 A047330
KEYWORD
easy,nonn
AUTHOR
Ctibor O. Zizka, May 23 2009
EXTENSIONS
2, 12 removed and sequence extended by R. J. Mathar, May 25 2009
STATUS
approved