%I #12 Sep 12 2017 15:15:47
%S 1,3,21,936340943,10460353197,9374251222371,23326283250291,
%T 615790788171551
%N Positive integers n such that 3^n == 6 (mod n).
%C No other terms below 10^15. - _Max Alekseyev_, Sep 12 2017
%o (PARI) isok(n) = Mod(3, n)^n == Mod(6, n);
%Y Solutions to 3^n == k (mod n): A277340 (k=-11), A277289 (k=-7), A277288 (k=-5), A015973 (k=-2), A015949 (k=-1), A067945 (k=1), A276671 (k=2), A276740 (k=5), this sequence (k=6), A277126 (k=7), A277630 (k=8), A277274 (k=11).
%K nonn,more
%O 1,2
%A _Dmitry Ezhov_, Oct 24 2016
%E a(6)-a(8) from _Max Alekseyev_, Sep 12 2017