A220788 Numbers k such that 7^k + 6^k is prime.

0, 1, 4, 16

Offset: 1

Author

Vincenzo Librandi, Jan 10 2013

Keywords

• nonn
• more

Comments

Next term is > 15000 if it exists.

Next term is > 100000 if it exists. - Michael S. Branicky, Oct 10 2024

Crossrefs

Cf. A062573, A074619.

Programs

Magma

/* The program does not work for n>2700: */ [n: n in [0..1000]| IsPrime(7^n + 6^n)];

Mathematica

Join[{0, 1}, Select[2 Range[500], PrimeQ[7^# + 6^#] &]]

PARI

for(n=0, 1000, if(isprime(7^n + 6^n), print1(n, ", ")))