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A098680 Primes p for which the period of reciprocal = (p-1)/13. 6
2393, 15497, 18149, 18617, 20021, 25819, 26183, 26339, 29303, 39937, 42953, 48491, 52313, 53327, 57331, 58189, 59021, 65183, 81953, 82499, 87491, 91703, 98047, 102233, 104287, 109097, 111229, 119419, 129793, 131171, 143287, 143833, 162007 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

Index entries for sequences related to decimal expansion of 1/n

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, 15000]], f[ # ] == 13 &]

CROSSREFS

Sequence in context: A172752 A020428 A100974 * A226149 A115931 A108055

Adjacent sequences:  A098677 A098678 A098679 * A098681 A098682 A098683

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Sep 15 2004

STATUS

approved

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Last modified December 17 21:13 EST 2014. Contains 252040 sequences.