This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A120115 #7 Apr 07 2021 03:32:45 %S A120115 19,31,43,47,67,71,79,139,223,251,263,307,311,359,379,419,463,491,563, %T A120115 571,587,619,691,739,751,811,887,907,967,971,983,1019,1031,1039,1051, %U A120115 1151,1163,1187,1223,1231,1279,1283,1291,1307,1319,1399,1423,1427,1439 %N A120115 Primes p that divide some Euler number E(k) for even k < p-1, but p does not divide E(p-1). %C A120115 See A092218 for a list of all primes that divide some E(k) for even k. %H A120115 Amiram Eldar, <a href="/A120115/b120115.txt">Table of n, a(n) for n = 1..1000</a> %t A120115 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 A120115 Cf. A000364, A092218. %K A120115 nonn %O A120115 1,1 %A A120115 _T. D. Noe_, Jun 09 2006