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 A084694 Squarefree numbers which are products of three consecutive numbers. I.e., squarefree numbers of the form k^3 - k. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No product of 4 consecutive numbers is squarefree. LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A007531(A007675(n)+2). - Amiram Eldar, Feb 25 2021 MATHEMATICA f[n_] := n*(n + 1)*(n + 2); f /@ Select[Range[250], AllTrue[# + {0, 1, 2}, SquareFreeQ] &] (* Amiram Eldar, Feb 25 2021 *) PROG (PARI) lista(nn) = {for (k=1, nn, if (issquarefree(x=k^3-k), print1(x, ", ")); ); } \\ Michel Marcus, Jul 29 2017 CROSSREFS Cf. A005117, A007531, A007675. Sequence in context: A346015 A001505 A327248 * A285149 A065945 A076715 Adjacent sequences: A084691 A084692 A084693 * A084695 A084696 A084697 KEYWORD nonn AUTHOR Amarnath Murthy, Jun 04 2003 EXTENSIONS Offset corrected to 1 by Michel Marcus, Jul 29 2017 STATUS approved

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Last modified May 19 07:05 EDT 2024. Contains 372666 sequences. (Running on oeis4.)