A273600 Numbers k such that (11^k - 8^k)/3 is prime.

2, 7, 11, 17, 37, 521, 877, 2423

Offset: 1

Author

Tim Johannes Ohrtmann, May 26 2016

Keywords

• nonn
• more
• hard

Comments

All terms are prime.

The corresponding primes: 19, 5796673, 92240578673, 167731742895202841, 113345629904382710526197539019199125641, ...

a(9) > 50000. - Michael S. Branicky, Nov 11 2024

Crossrefs

Cf. A005808, A210506, A128027, A216181, A128347, A273598, A273599, A273601, A062577.

Programs

Mathematica

Select[Range[1, 10000], PrimeQ[(11^# - 8^#)/3] &]

PARI

for(n=1, 10000, if(isprime((11^n - 8^n)/3), print1(n, ", ")))