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A145643
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Cubefree part of n!!.
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2
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1, 2, 3, 1, 15, 6, 105, 6, 35, 60, 385, 90, 5005, 1260, 75075, 315, 1276275, 210, 24249225, 525, 509233725, 11550, 11712375675, 34650, 2342475135, 900900, 2342475135, 3153150, 67931778915, 28028, 2105885146365, 14014, 2573859623335
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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CubefreePart[n_Integer?Positive] := Times @@ Power @@@ ({#[[1]], Mod[ #[[2]], 3]} & /@ FactorInteger[n]); Table[CubefreePart[n!! ], {n, 1, 40}]
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PROG
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(Python)
from sympy import factorint, prod
return 1 if n <= 1 else prod(p**(e % 3) for p, e in factorint(prod(range(n, 0, -2))).items())
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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