A382869 Numbers k >= 1 such that A018804(k) is a Fibonacci number (A000045).

1, 2, 3, 4, 7, 9, 11, 1751, 2031, 45012, 105772, 1266256, 1490601, 1774525

Offset: 1

Author

Ctibor O. Zizka, Apr 07 2025

Keywords

• nonn
• more

Examples

			For k = 4: A018804(4) = 8, 8 is a Fibonacci number, thus 4 is a term.
		

Crossrefs

Cf. A000045, A018804.

Similar sequence : A005382.

Programs

Mathematica

fibQ[n_] := Or @@ IntegerQ /@ Sqrt[5*n^2 + {-4, 4}]; f[p_, e_] := (e*(p - 1)/p + 1)*p^e; q[n_] := fibQ[Times @@ f @@@ FactorInteger[n]]; Select[Range[120000], q] (* Amiram Eldar, Apr 07 2025 *)

Extensions

a(10)-a(14) from Amiram Eldar, Apr 07 2025