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A341183 Numbers k such that (30*k)^4 + 1 is prime.

%I A341183 #20 Mar 07 2021 18:50:15
%S A341183 3,6,7,18,20,23,27,31,39,40,55,56,57,68,75,80,88,90,101,103,113,115,
%T A341183 116,124,126,129,132,136,139,148,153,163,165,173,194,203,211,215,218,
%U A341183 232,260,277,284,285,288,290,293,302,309,336,344,347,357,358,362,368,377,390,394,397,401
%N A341183 Numbers k such that (30*k)^4 + 1 is prime.
%C A341183 This is the third sequence in a family defined by this same condition, when generalized as (30*k)^(2^m).
%C A341183 A111175 and A138220 are the first and second sequences in this family, with m = 0 and m = 1, respectively.
%t A341183 (* This program gives some results for each member of the family for m up to 10. *)
%t A341183 Do[resultk = {};
%t A341183 Do[
%t A341183   r = (30 k)^(2^m) + 1;
%t A341183   If[PrimeQ[r], AppendTo[resultk, k]];
%t A341183   , {k, 1, 1000}];
%t A341183 If[Length[resultk] > 0, Print[{m, 2^m, resultk}]], {m, 0, 10}]
%o A341183 (PARI) isok(k) = isprime((30*k)^4 + 1); \\ _Michel Marcus_, Feb 13 2021
%Y A341183 Cf. A111175, A138220.
%K A341183 nonn
%O A341183 1,1
%A A341183 _Richard R. Forberg_, Feb 06 2021