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A128364
a(n) = least k such that the remainder when 24^k is divided by k is n.
17
23, 11, 7, 5, 19, 10, 17, 142, 15, 566, 13, 78, 5865637, 205, 13809, 20, 589, 39, 35, 278, 129, 554, 459207143, 25, 148731221, 50, 63, 274, 2855, 33, 49, 34, 5429, 542, 5528521301, 42, 2773, 538, 185, 77, 3220589, 66, 90553, 956, 2317, 70, 161, 104
OFFSET
1,1
MATHEMATICA
t = Table[0, {10000}]; k = 1; While[k < 3600000000, a = PowerMod[25, k, k]; If[a < 10001 && t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++ ]; t (* Robert G. Wilson v, Jun 29 2009 *)
lk[n_] := Module[{k = 1}, While[PowerMod[24, k, k] != n, k++]; k]; Array[ lk, 48] (* Harvey P. Dale, Jan 18 2019 *)
KEYWORD
hard,nonn
AUTHOR
Alexander Adamchuk, Feb 27 2007
EXTENSIONS
a(13) - a(34) from Robert G. Wilson v, Jun 29 2009
STATUS
approved