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%I #5 Jul 23 2015 17:45:54
%S 3,5,17,257,1093,3511,65537,1006003
%N Primes p such that A001221(p-1)^(p-1) == 1 (mod p^2).
%C No further terms up to 10^9.
%C All currently (as of 2015-07-23) known terms of A001220 and A019434 are in the sequence, as is A014127(2), but A014127(1) is not.
%e A001221(1092) == 4 and 4^1092 == 1 (mod 1093^2), so 1093 is a term of the sequence.
%o (PARI) forprime(p=1, 1e9, if(Mod(omega(p-1), p^2)^(p-1)==1, print1(p, ", ")))
%Y Cf. A001220, A014127, A019434, A244546.
%K nonn,hard,more
%O 1,1
%A _Felix Fröhlich_, Jul 23 2015