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A127816
a(n) = least k >= 1 such that the remainder when 6^k is divided by k is n.
38
5, 34, 213, 68, 4021227877, 7, 121129, 14, 69, 26, 767, 51, 6191, 22, 201, 20, 1919, 33, 169, 44, 39, 1778, 1926049, 174, 2673413, 50, 63, 451, 1257243481237, 93, 851, 316, 183, 14809, 1969, 38, 1362959, 1826, 177, 289, 65, 87, 5567, 1252, 57, 1651, 6403249
OFFSET
1,1
COMMENTS
a(7^k-1) = 7^k.
FORMULA
a(7^k-1) = 7^k.
MATHEMATICA
t = Table[0, {10000}]; k = 1; lst = {}; While[k < 5600000000, a = PowerMod[6, k, k]; If[ a<10001 && t[[a]]==0, t[[a]]=k; Print[{a, k}]]; k++ ]; t
KEYWORD
hard,nonn
AUTHOR
Alexander Adamchuk, Jan 30 2007, Feb 05 2007
EXTENSIONS
a(5) from Joe K. Crump confirmed and a(6)-a(28) added by Ryan Propper, Feb 21 2007
I combined the two Mathematica codings into one and extended the search limits. - Robert G. Wilson v, Jul 16 2009
a(29) as conjectured by J. K. Crump confirmed by Hagen von Eitzen, Jul 21 2009
Corrected authorship of the a-file - R. J. Mathar, Aug 24 2009
STATUS
approved