A273937 Numbers n such that 7^n - 6^(n+1) is prime.

49, 90, 206, 314, 375, 578, 949, 2883, 2959, 3133, 3409, 6174, 6185, 16461, 22313, 24462, 30249, 45317, 58169, 60309, 79202

Offset: 1

Author

Robert Price, Jun 04 2016

Keywords

• nonn
• more

Comments

a(22) > 10^5. - Robert Price, May 04 2016

Crossrefs

Cf. A093765.

Programs

Mathematica

Select[Range[12, 100000], PrimeQ[7^# - 6^(# + 1)] &]

PARI

is(n)=ispseudoprime(7^n-6^(n+1)) \\ Charles R Greathouse IV, Jun 08 2016