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Positive integers n such that 3^n == 11 (mod n).
8

%I #30 Oct 12 2016 22:58:31

%S 1,2,1162,1692934,3851999,274422823,14543645261,492230729674,

%T 773046873382,13010754158393,31446154470014,583396812890467,

%U 598371102650063

%N Positive integers n such that 3^n == 11 (mod n).

%C No other terms below 10^15. Some larger terms: 38726095838775708310162, 2682806839696008709567739369. - _Max Alekseyev_, Oct 12 2016

%e 3 == 11 mod 1, so 1 is a term.

%e 9 == 11 mod 2, so 2 is a term.

%t k = 3; lst = {1, 2}; While[k < 12000000001, If[ PowerMod[3, k, k] == 11, AppendTo[lst, k]]; k++]; lst (* _Robert G. Wilson v_, Oct 08 2016 *)

%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), A277126 (k=7), this sequence (k=11).

%K nonn,more

%O 1,2

%A _Seiichi Manyama_, Oct 08 2016

%E a(7)-a(13) from _Max Alekseyev_, Oct 12 2016