A227171 Numbers n such that (18^n + 17^n)/35 is prime.

3, 47, 53, 2411, 4057, 7963, 10273, 15737, 53299

Offset: 1

Author

Jean-Louis Charton, Jul 03 2013

Keywords

• hard
• nonn
• more

Comments

All terms are prime.

Crossrefs

Cf. A000978, A057469, A128066, A128335, A128336, A187805, A181141, A187819, A217095.

Programs

PARI

is(n)=ispseudoprime((18^n+17^n)/35) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(7), a(8) from Richard Fischer, Aug 18 2013

a(9) from Robert Price, Aug 25 2013