A059709 Numbers k such that A003266(k) - 1 is prime.

4, 5, 6, 7, 8, 14, 15

Offset: 1

Author

Robert G. Wilson v, Feb 07 2001

Keywords

• nonn
• more

Comments

The a(n)-th almost-Fibonorial number is prime.

If it exists, a(8) > 1300. - Michael S. Branicky, Aug 17 2024

Links

• C. K. Caldwell, Fibonacci Numbers.
• Eric Weisstein's World of Mathematics, Fibonorial.

Crossrefs

Cf. A003266, A053408.

Programs

Mathematica

a = 1; Do[ a = a*Fibonacci[n]; If[ PrimeQ[a - 1], Print[n] ], {n, 1, 247} ]

Extensions

Definition corrected by Daniel Forgues, Nov 29 2009

Name edited by Michel Marcus, Jan 17 2024