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A128363
a(n) = least k such that the remainder when 23^k is divided by k is n.
17
2, 3, 5, 19, 262, 17, 58, 9, 10, 13, 14, 55, 86, 12153, 514, 111823, 95, 25, 30, 12147, 68, 235, 29, 280517, 56, 27, 502, 16805, 51, 49, 166, 35, 62, 1837, 38, 977969, 82, 39, 1370, 289, 122, 9822698929535, 65, 133, 697, 161, 303, 19445, 50, 147, 259, 1247
OFFSET
1,1
MATHEMATICA
t = Table[0, {10000} ]; k = 1; While[ k < 4000000000, a = PowerMod[23, k, k]; If[a < 10001 && t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++ ]; t (* Robert G. Wilson v, Aug 04 2009 *)
KEYWORD
hard,nonn
AUTHOR
Alexander Adamchuk, Feb 27 2007
EXTENSIONS
a(42), a(64) from Hagen von Eitzen, Aug 04 2009
a(750), a(770), a(234), a(274), a(406), a(600), a(610), a(754) from Daniel Morel, May 31, Aug 24, Sep 20 2010
a(84) from Max Alekseyev, Apr 13 2012
STATUS
approved