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A197226
The period of the decimal fraction 1/A197225(n).
2
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
OFFSET
1,2
COMMENTS
These numbers are prime powers, members of A000961.
LINKS
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
KEYWORD
nonn,base
AUTHOR
T. D. Noe, Oct 22 2011
STATUS
approved