A059454 Numbers k such that 2*3^k - 7 is prime.

2, 3, 5, 6, 9, 14, 39, 51, 73, 101, 155, 183, 286, 291, 310, 313, 335, 570, 951, 1011, 1183, 1930, 2586, 3423, 6486, 7791, 11586, 14290, 18590, 29595, 35286, 76311

Offset: 1

Author

Robert G. Wilson v, Feb 15 2001

Keywords

• nonn
• more

Crossrefs

Cf. A059326 (2*3^k + 7 is prime).

Programs

Magma

[n: n in [1..1000] | IsPrime(2*3^n-7)]; // Jinyuan Wang, Jan 20 2020

Mathematica

Do[ If[ PrimeQ[ 2*3^n - 7 ], Print[n] ], {n, 1, 5700} ]

PARI

is(n)=ispseudoprime(2*3^n-7) \\ Charles R Greathouse IV, May 22 2017

Extensions

First term 0 removed by Georg Fischer, Aug 01 2019

a(27)-a(30) from Jinyuan Wang, Jan 20 2020

a(31) from Michael S. Branicky, May 20 2023

a(32) from Michael S. Branicky, Jul 28 2024