A242176 Numbers k such that k*6^k + 1 is prime.

1, 2, 91, 185, 387, 488, 747, 800, 9901, 10115, 12043, 13118, 30981, 51496

Offset: 1

Author

Vincenzo Librandi, May 08 2014

Keywords

• nonn
• more

Links

• G. Loeh, Generalized Cullen primes

Crossrefs

Cf. numbers n such that n*k^n + 1 is prime: A005849 (k=2), A006552 (k=3), A007646 (k=4), this sequence (k=6), A242177 (k=7), A242178 (k=8), A007647 (k=10), A242196 (k=12), A242197 (k=14), A242198 (k=15), A242199 (k=16), A007648 (k=18).

Programs

Magma

[n: n in [0..1500] | IsPrime(n*6^n+1)];

Mathematica

Select[Range[1500], PrimeQ[# 6^# + 1] &]

PARI

is(n)=ispseudoprime(n*6^n+1) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(9)-a(14) from Loeh's list (see Links) - Bruno Berselli, May 08 2014