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%I #16 Jul 31 2015 20:47:18
%S 29,7,26997,13,8471,33,23,11,721,55,19,39,17,886,21,26,803,98,13289,
%T 22,51,878,1141,146,35,38,111,218,515267673651961,31,3212679202339,56,
%U 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
%N a(n) = least k such that the remainder of 30^k divided by k is n.
%H Robert G. Wilson v et al., <a href="/A128370/a128370_2.txt">Table of n, a(n) for n = 1..10000 with -1 for large entries where a(n) has not yet been found</a>
%t 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 *)
%Y Cf. A128361, A128362, A128363, A128364, A128365, A128366, A128367, A128368, A129369, A128371, A128372.
%Y Cf. A036236, A078457, A119678, A119679, A127816, A119715, A119714, A127817, A127818, A127819, A127820, A127821, A128154, A128155, A128156, A128157, A128158, A128159, A128160.
%Y Cf. A128149, A128150, A128172.
%K nonn
%O 1,1
%A _Alexander Adamchuk_, Feb 27 2007
%E Terms a(29) onward from _Max Alekseyev_, Mar 22 2012