A096185 - OEIS

%I #13 Mar 12 2023 05:08:11

%S 3,4,8,9,16,25,33,40,116,201,208,504,579,964,1060,1160,1508,1969,4615,

%T 7311,65964,83121,87396

%N Numbers k such that 7^k + 6^(k-1) is prime.

%C a(24) > 10^5. - _Robert Price_, Mar 23 2016

%t Do[ If[ PrimeQ[7^n + 6^(n - 1)], Print[n]], {n, 4000}]

%o (PARI) lista(nn) = {for(n=1, nn, if(ispseudoprime(7^n+6^(n-1)), print1(n, ", "))); } \\ _Altug Alkan_, Mar 23 2016

%Y Cf. A082103, A093717, A093793, A093765, A093794, A093795, A096186.

%K nonn,more

%O 1,1

%A Herman H. Rosenfeld (herm3(AT)pacbell.net) and _Robert G. Wilson v_, Jun 18 2004

%E a(19)-a(23) from _Robert Price_, Mar 23 2016