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A229882
Squarefree oblong numbers.
3
2, 6, 30, 42, 110, 182, 210, 462, 506, 870, 930, 1122, 1190, 1406, 1482, 1722, 1806, 2162, 3306, 3422, 3782, 4290, 4422, 4830, 4970, 5402, 6006, 6162, 6806, 7310, 7482, 8742, 8930, 10302, 10506, 11130, 11342, 11990, 12210, 12882, 13110, 14042, 15006, 16770, 17030
OFFSET
1,1
COMMENTS
Oblong numbers that are squarefree numbers.
LINKS
FORMULA
Intersection of A002378 and A005117. - Joerg Arndt, Oct 03 2013
a(n) = A007674(n)^2 + A007674(n). - Charles R Greathouse IV, Oct 04 2013
MATHEMATICA
Select[#*(# + 1) & /@ Range[150], SquareFreeQ] (* Amiram Eldar, Feb 22 2021 *)
PROG
(PARI) for(n=1, 1e4, if(issquarefree(n) && issquarefree(n+1), print1(n*(n+1)", "))) \\ Charles R Greathouse IV, Mar 18 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Irina Gerasimova, Oct 02 2013
EXTENSIONS
Wrong term removed and more terms added by Amiram Eldar, Feb 22 2021
STATUS
approved