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A270927 Smallest k such that k*n^m + 1 is prime, case m=4.

%I A270927 #18 Dec 23 2024 14:53:44
%S A270927 1,1,2,1,18,1,6,3,6,7,46,5,10,3,8,1,16,2,28,1,2,7,16,1,24,12,10,1,10,
%T A270927 2,6,7,26,1,12,3,6,3,8,16,10,3,22,16,2,1,6,1,36,3,6,3,16,1,18,1,8,12,
%U A270927 16,10,12,31,2,10,22,2,36,21,40,6,12,18,6,1,6,7,10,2,18,1,2,1,22,2,12,18,6,1,18,1,58,3,12,7,24,2,16,3,16,6,6,7,46,25,2,1,12,7,18,12,46,3,12,5,10,3,48,1,16,2
%N A270927 Smallest k such that k*n^m + 1 is prime, case m=4.
%H A270927 Zak Seidov, <a href="/A270927/b270927.txt">Table of n, a(n) for n = 1..10000</a>
%H A270927 Zak Seidov,<a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2016-March/016251.html">20 related sequences</a>.
%t A270927 With[{m = 4, nn = 120}, Table[SelectFirst[Range@ nn, PrimeQ[# n^m + 1] &], {n, nn}]] (* _Michael De Vlieger_, Mar 26 2016, Version 10 *)
%t A270927 sk[n_]:=Module[{k=1,c=n^4},While[!PrimeQ[k*c+1],k++];k]; Array[sk,120] (* _Harvey P. Dale_, Jun 05 2021 *)
%o A270927 (PARI) {m=4;for(n=1,10000,k=1;while(!isprime(k*n^m+1),k++);
%o A270927 write("b270927.txt",n" "k))} \\ for b-file - _Zak Seidov_, Mar 26 2016
%Y A270927 Cf. A034693 (m=1), A035092 (m=2), A238847 (m=3).
%K A270927 nonn
%O A270927 1,3
%A A270927 _Zak Seidov_, Mar 26 2016