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%I #19 Mar 25 2023 08:20:04
%S 3,5,7,81,185,254,623,1087,2407,7862,8721,9353,13154
%N Numbers k such that 11^(k+7) + 7^(k+5) + 5^(k+3) + 3^(k+2) + 2^(k+1) + 1 is prime.
%C a(14) > 41000. - _Michael S. Branicky_, Mar 25 2023
%t ParallelMap[If[PrimeQ[11^(#+7) + 7^(#+5) + 5^(#+3) + 3^(#+2) + 2^(#+1) + 1], #, Nothing] &, Range@8000]
%o (PARI) is(n) = ispseudoprime(11^(n+7) + 7^(n+5) + 5^(n+3) + 3^(n+2) + 2^(n+1) + 1) \\ _Felix Fröhlich_, Mar 06 2019
%K nonn,more,hard
%O 1,1
%A _Mikk Heidemaa_, Feb 24 2019
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