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A056216
Primes p whose period of reciprocal equals (p-1)/11.
12
353, 3499, 10429, 13619, 15269, 20219, 20593, 23057, 23189, 24091, 25741, 30713, 35509, 38567, 45233, 49171, 57179, 57223, 60149, 63691, 63977, 67783, 77023, 85229, 88463, 90619, 91367, 93941, 96779, 108967, 109913, 110221, 112069
OFFSET
1,1
COMMENTS
Cyclic numbers of the eleventh degree (or eleventh order): the reciprocals of these numbers belong to one of eleven different cycles. Each cycle has the (number minus 1)/11 digits.
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, 11000]], f[ # ] == 11 &]
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, Aug 02 2000
EXTENSIONS
Edited by N. J. A. Sloane, Apr 30 2007
STATUS
approved