cp's OEIS Frontend

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.

A327468 Numbers m that divide 8^m + 7.

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%I A327468 #34 Feb 07 2024 09:02:39
%S A327468 1,3,5,25,519,290502305,821808425,979288025,982989263,25783323897,
%T A327468 27771237541,31045665345,65130752425,3708883906025,15079242289703,
%U A327468 973336048301405
%N A327468 Numbers m that divide 8^m + 7.
%C A327468 Conjecture: For k > 1, k^m == 1-k (mod m) has an infinite number of positive solutions.
%C A327468 Integer m not divisible by 3 is a term if and only if 3m is a term of A240941. - _Max Alekseyev_, Feb 07 2024
%C A327468 Also terms 930486448009391617725 and 21036656390681764555645540794214294457925. - _Giovanni Resta_, Oct 04 2019
%C A327468 Other terms 71245661271703622047, 7093208961478946798805, 7807963392818324067361574236385. - _Max Alekseyev_, Feb 07 2024
%o A327468 (PARI) isok(n) = Mod(8, n)^n==-7; \\ _Michel Marcus_, Oct 05 2019
%o A327468 (Magma) [m: m in [1..7] | (8^m + 7) mod m eq 0] cat [m: m in [8..10^8] | Modexp(8, m, m) + 7 eq m]; // _Jon E. Schoenfield_, Oct 05 2019
%Y A327468 Solutions to k^m == 1-k (mod m): 1 (k = 1), A006521 (k = 2), A015973 (k = 3), A327840 (k = 4), A123047 (k = 5), A327943 (k = 6), A328033 (k = 7), this sequence (k = 8).
%Y A327468 Cf. A240941, A253211.
%K A327468 nonn,more
%O A327468 1,2
%A A327468 _Juri-Stepan Gerasimov_, Oct 04 2019
%E A327468 a(10)-a(13) from _Giovanni Resta_, Oct 04 2019
%E A327468 a(14)-a(16) from _Max Alekseyev_, Feb 07 2024