A271883 Numbers n such that 9^n-8^(n-1) is prime.

2, 22, 58, 496, 2740

Offset: 1

Author

Robert Price, Apr 16 2016

Keywords

• nonn
• more

Comments

a(6) > 10^5.

Examples

			2 is a member since 9^2 - 8^1 =  81 - 8 = 73 which is a prime number.
		

Crossrefs

Cf. A093713, A082103, A093717, A093793, A096185, A093794, A093795, A096186.

Programs

Mathematica

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

PARI

lista(nn) = for(n=1, nn, if(ispseudoprime(9^n-8^(n-1)), print1(n, ", "))); \\ Altug Alkan, Apr 16 2016