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A127991
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2*n^3 - 2*n + 9 divided by 3*largest prime factor.
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3
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1, 1, 1, 1, 1, 11, 1, 3, 21, 39, 1, 31, 1, 1, 1, 7, 297, 9, 351, 1, 1, 19, 91, 1, 101, 141, 51, 33, 37, 49, 1, 299, 37, 1, 3, 39, 21, 1, 11, 1, 19, 1, 31, 1071, 351, 9, 43, 1, 481, 11, 511, 83, 3, 3, 69, 1, 1, 91, 1, 19, 187, 39, 219, 417, 553, 37, 1, 1, 1, 1369, 117, 693, 423, 31
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OFFSET
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1,6
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LINKS
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FORMULA
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MATHEMATICA
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a = {}; Do[AppendTo[a, 2n^3 - 2n + 9], {n, 1, 300}]; b = {}; Do[c = FactorInteger[a[[n]]]; d = c[[Length[c]]]; AppendTo[b, a[[n]]/(3 d[[1]])], {n, 1, Length[a]}]; b
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PROG
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(PARI) gpf(n)=my(f=factor(n)[, 1]); if(n==1, 1, f[#f]);
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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