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A128365
a(n) = least k such that the remainder when 25^k is divided by k is n.
17
2, 23, 11, 7, 10, 19, 57, 17, 14, 15, 614, 13, 34
OFFSET
1,1
COMMENTS
a(14) > 10^15. - Max Alekseyev, Apr 14 2012
LINKS
MATHEMATICA
t = Table[0, {10000} ]; k = 1; While[ k < 4000000000, a = PowerMod[25, 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,more,nonn
AUTHOR
Alexander Adamchuk, Feb 27 2007
STATUS
approved