A059670 Numbers k such that F(k)*2^k + 1 (A006483) is prime, where F(k) is the k-th Fibonacci number.

1, 2, 3, 13, 16, 20, 28, 83, 136, 300, 765, 1005, 1395, 3333, 30259

Offset

1,2

Comments

a(15) > 17000. - Michael S. Branicky, Oct 02 2022

Links

Table of n, a(n) for n=1..15.

Mathematica

Do[ If[ PrimeQ[ Fibonacci[ n ]*2^n + 1 ], Print[ n ] ], {n, 1, 3000} ]

Prog

(Python)
from sympy import fibonacci, isprime
def ok(n): return isprime(fibonacci(n)*2**n + 1)
print([k for k in range(1400) if ok(k)]) # Michael S. Branicky, Oct 01 2022

Crossrefs

Cf. A000045, A006483.

Sequence in context: A273617 A101541 A299543 * A038975 A059456 A274589

Adjacent sequences: A059667 A059668 A059669 * A059671 A059672 A059673

Keyword

nonn,more

Author

Robert G. Wilson v, Feb 05 2001

Extensions

a(14) from Michael S. Branicky, Oct 02 2022

a(15) from Michael S. Branicky, May 29 2023

Status

approved