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 A056214 Primes p for which the period of reciprocal = (p-1)/9. 2
 73, 1423, 1459, 2377, 2503, 3457, 7741, 9433, 10891, 10909, 16057, 17299, 17623, 20269, 21313, 22699, 24103, 26263, 28621, 28927, 29629, 30817, 32257, 34273, 34327, 35461, 35731, 36343, 36793, 37549, 37567, 37657, 38737, 39367, 39979 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Cyclic numbers of the ninth degree (or ninth order): the reciprocals of these numbers belong to one of nine different cycles. Each cycle has the (number minus 1)/9 digits. LINKS MATHEMATICA f[n_Integer] := Block[{ds = Divisors[n - 1]}, (n - 1)/Take[ ds, Position[ PowerMod[ 10, ds, n], 1] [[1, 1]]] [[ -1]]]; Select[ Prime[ Range[4, 5000]], f[ # ] == 9 &] CROSSREFS Sequence in context: A221479 A253263 A098676 * A197216 A197502 A197241 Adjacent sequences:  A056211 A056212 A056213 * A056215 A056216 A056217 KEYWORD nonn,base AUTHOR Robert G. Wilson v, Aug 02 2000 EXTENSIONS Edited by N. J. A. Sloane, Apr 30 2007 STATUS approved

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Last modified May 25 16:40 EDT 2020. Contains 334595 sequences. (Running on oeis4.)