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A145644
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Cubefree part of 10^n.
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0
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1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100, 1, 10, 100
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OFFSET
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0,2
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COMMENTS
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Period 3: repeat [1, 10, 100].
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LINKS
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FORMULA
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G.f.: (1+10*x+100*x^2)/(1-x^3).
a(n) = a(n-3). (End)
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MATHEMATICA
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CubefreePart[n_Integer?Positive] := Times @@ Power @@@ ({#[[1]], Mod[ #[[2]], 3]} & /@ FactorInteger[n]); Table[CubefreePart[10^n], {n, 1, 40}]
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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