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A197226 The period of the decimal fraction 1/A197225(n). 1
1, 2, 16, 3, 5, 13, 8, 13, 41, 4, 53, 8, 81, 43, 113, 7, 256, 5, 79, 173, 32, 179, 32, 233, 239, 281, 293, 32, 107, 359, 61, 125, 27, 193, 199, 419, 151, 103, 593, 41, 641, 653, 659, 32, 719, 373, 761, 271, 409, 313, 953, 331, 1013, 1019, 137, 619, 223, 31 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

These numbers are prime powers, members of A000961.

LINKS

Table of n, a(n) for n=1..58.

MATHEMATICA

myPerfectPowerQ[n_] := Length[FactorInteger[n]] == 1; t=Select[Prime[Range[500]], Mod[10, #] > 0 && myPerfectPowerQ[Length[RealDigits[1/#, 10][[1, 1]]]] &]; Table[Length[RealDigits[1/n, 10][[1, 1]]], {n, t}]

CROSSREFS

Sequence in context: A217028 A145684 A254637 * A141239 A303990 A095860

Adjacent sequences:  A197223 A197224 A197225 * A197227 A197228 A197229

KEYWORD

nonn,base

AUTHOR

T. D. Noe, Oct 22 2011

STATUS

approved

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Last modified March 18 22:10 EDT 2019. Contains 321305 sequences. (Running on oeis4.)