A274239 Numbers n such that 9^n + 8^(n+1) is prime.

1, 2, 5, 20, 53, 161, 380, 500, 530, 698, 832, 833, 6353, 25433, 53921, 73538

Offset: 1

Author

Robert Price, Jun 15 2016

Keywords

• nonn
• more

Comments

a(17) > 10^5.

Crossrefs

Cf. A093765.

Programs

Magma

[n: n in [0..500] | IsPrime(9^n+8^(n+1))]; // Vincenzo Librandi, Jul 12 2016

Mathematica

Select[Range[0,100000], PrimeQ[9^# + 8^(# + 1)] &]

PARI

is(n)=ispseudoprime(9^n+8^(n+1)) \\ Charles R Greathouse IV, Jun 13 2017