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%I #7 Apr 07 2021 03:32:45
%S 19,31,43,47,67,71,79,139,223,251,263,307,311,359,379,419,463,491,563,
%T 571,587,619,691,739,751,811,887,907,967,971,983,1019,1031,1039,1051,
%U 1151,1163,1187,1223,1231,1279,1283,1291,1307,1319,1399,1423,1427,1439
%N Primes p that divide some Euler number E(k) for even k < p-1, but p does not divide E(p-1).
%C See A092218 for a list of all primes that divide some E(k) for even k.
%H Amiram Eldar, <a href="/A120115/b120115.txt">Table of n, a(n) for n = 1..1000</a>
%t q[n_] := PrimeQ[n] && ! Divisible[EulerE[n - 1], n] && AnyTrue[Range[2, n - 2, 2], Divisible[EulerE[#], n] &]; Select[Range[1500], q] (* _Amiram Eldar_, Apr 07 2021 *)
%Y Cf. A000364, A092218.
%K nonn
%O 1,1
%A _T. D. Noe_, Jun 09 2006