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%I #12 May 21 2018 03:24:48
%S 1,22,33,39,43,62,74,134,142,167,212,238,287,313,335,369,414,415,418,
%T 432,509,604,679,697,770,782,815,859,874,895,897,924,1039,1048,1070,
%U 1085,1134,1145,1170,1177,1212,1239,1240,1262,1339,1347,1364,1374,1407,1413,1414,1449
%N Numbers n such that Phi_25(n) is prime, where Phi is the cyclotomic polynomial.
%H G. C. Greubel, <a href="/A250180/b250180.txt">Table of n, a(n) for n = 1..10000</a>
%t a250180[n_] := Select[Range[n], PrimeQ@Cyclotomic[25, #] &]; a250180[256]
%o (PARI) isok(n) = isprime(polcyclo(25, n)); \\ _Michel Marcus_, Dec 27 2014
%Y See A250177 for references.
%K nonn
%O 1,2
%A _Eric Chen_, Dec 26 2014