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A128370
a(n) = least k such that the remainder of 30^k divided by k is n.
7
29, 7, 26997, 13, 8471, 33, 23, 11, 721, 55, 19, 39, 17, 886, 21, 26, 803, 98, 13289, 22, 51, 878, 1141, 146, 35, 38, 111, 218, 515267673651961, 31, 3212679202339, 56, 267, 866, 4367, 42, 10129, 862, 57, 86, 42691, 13479, 949, 214, 95, 77, 7633, 52, 1469, 170, 429, 68, 2791229, 94, 215, 422, 3849, 842, 9773, 140
OFFSET
1,1
MATHEMATICA
t = Table[0, {10000} ]; k = 1; While[ k < 5100000000, a = PowerMod[30, k, k]; If[a < 10001 && t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++ ]; t (* Robert G. Wilson v, Aug 06 2009 *)
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Feb 27 2007
EXTENSIONS
Terms a(29) onward from Max Alekseyev, Mar 22 2012
STATUS
approved