A130331 Number of divisors of A123240(n).

4, 4, 4, 6, 4, 4, 6, 6, 4, 4, 4, 4, 6, 6, 4, 4, 4, 9, 4, 4, 6, 6, 4, 10, 6, 4, 6, 4, 4, 4, 12, 4, 6, 7, 4, 6, 4, 12, 4, 6, 6, 4, 10, 4, 12, 4, 4, 4, 12, 4, 6, 4, 4, 4, 12, 6, 6, 9, 4, 12, 4, 10, 4, 6, 6, 4, 4, 16, 4, 4, 6, 4, 12, 4, 12, 4, 4, 12, 4, 4, 4, 15, 4, 4, 6, 6, 12, 6, 4, 12, 4, 4, 12, 4, 10, 6, 4

Offset

1,1

Comments

By definition, each term is in A001690. - R. J. Mathar, Jan 15 2008

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Formula

a(n) = A000005(A123240(n)). - R. J. Mathar, Jan 15 2008

Mathematica

seq[max_] := Module[{d = DivisorSigma[0, Range[max]], dmax, k = 2}, dmax = Max[d]; While[Fibonacci[k] < dmax, k++]; Select[d, !MemberQ[Fibonacci[Range[2, k]], #] &]]; seq[300] (* Amiram Eldar, Apr 08 2024 *)

Crossrefs

Cf. A000005, A000379, A123240.

Sequence in context: A010304 A164821 A348677 * A141241 A140696 A160401

Adjacent sequences: A130328 A130329 A130330 * A130332 A130333 A130334

Keyword

easy,nonn

Author

Giovanni Teofilatto, Aug 07 2007

Extensions

More terms from R. J. Mathar, Jan 15 2008

Status

approved