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A084694
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Squarefree numbers which are products of three consecutive numbers. I.e., squarefree numbers of the form k^3 - k.
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1
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6, 210, 2730, 10626, 26970, 39270, 54834, 74046, 195054, 287430, 342930, 474474, 635970, 830490, 1061106, 1190910, 1330890, 1481430, 2196870, 2627934, 2863146, 3944154, 4574130, 5639574, 6028386, 6434670, 7301190, 8242206, 9260790
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OFFSET
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1,1
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COMMENTS
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No product of 4 consecutive numbers is squarefree.
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LINKS
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FORMULA
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MATHEMATICA
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f[n_] := n*(n + 1)*(n + 2); f /@ Select[Range[250], AllTrue[# + {0, 1, 2}, SquareFreeQ] &] (* Amiram Eldar, Feb 25 2021 *)
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PROG
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(PARI) lista(nn) = {for (k=1, nn, if (issquarefree(x=k^3-k), print1(x, ", ")); ); } \\ Michel Marcus, Jul 29 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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