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A328033
Numbers m that divide 7^m + 6.
3
1, 13, 793, 1943, 150341, 183793, 2348789, 26052527, 27982637, 54789869, 1588344433, 3928538029, 8115802931, 16936276919, 17786709541, 47778790033, 973094452518029
OFFSET
1,2
COMMENTS
Conjecture: For k > 1, k^m == 1 - k (mod m) has infinite number of positive solutions.
Also includes 2073273696480171732497. - Giovanni Resta, Oct 04 2019
PROG
(Magma) [1] cat [n: n in [1..10^8] | Modexp(7, n, n) + 6 eq n];
CROSSREFS
Solutions to k^m == 1-k (mod m): A006521 (k = 2), A015973 (k = 3), A327840 (k = 4), A123047 (k = 5), A327943 (k = 6), this sequence (k = 7), A327468 (k = 8).
Cf. A253210 (7^n + 6).
Sequence in context: A301644 A182932 A221934 * A366559 A316673 A319509
KEYWORD
nonn,more
AUTHOR
EXTENSIONS
a(12)-a(16) from Giovanni Resta, Oct 04 2019
a(17) from Max Alekseyev, Feb 07 2024
STATUS
approved