A221637 Numbers n such that (15^n + 14^n)/29 is prime.

3, 127, 227, 1009, 1951, 5101, 14011

Offset: 1

Author

Robert Price, May 28 2013

Keywords

• hard
• nonn
• more

Comments

All terms are prime.

a(8) > 10^5.

Crossrefs

Cf. A057180, A128072, A128343, A181141, A187819, A217095, A185239, A213216, A225191, A225097.

Programs

Mathematica

Select[ Prime[ Range[1, 100000] ], PrimeQ[ (15^# + 14^#)/29 ]& ]

PARI

is(n)=ispseudoprime((15^n+14^n)/29) \\ Charles R Greathouse IV, Feb 20 2017