%I #13 Aug 21 2021 19:55:30
%S 301,737,1505,1655,2107,3197,3311,3913,5117,5159,5219,5719,6275,6923,
%T 7385,7513,7525,8107,8275,8729,9331,9581,9835,10535,10849,11137,11585,
%U 12341,12529,12943,13301,14003,14147,14749,15953,15985,17759,18361
%N Numbers k such that k divides the numerator of B(2k) (the Bernoulli numbers), but gcd(3k, 8^k+1) > 3.
%C Equivalently, k is in A069040 but not in A070191.
%t testb[n_] := Select[First/@FactorInteger[n], Mod[2n, #-1]==0&]=={}; test8[n_] := GCD[3n, PowerMod[8, n, 3n]+1]==3; Select[Range[19000], testb[ # ]&&!test8[ # ]&]
%Y Cf. A069040, A070191, A070193.
%K nonn,more
%O 1,1
%A _Benoit Cloitre_ and _Dean Hickerson_, Apr 26 2002