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A228140
Numbers n such that n^2 - 2 is not squarefree.
3
10, 39, 45, 58, 59, 88, 108, 116, 137, 156, 157, 186, 206, 235, 244, 255, 284, 304, 333, 334, 338, 353, 373, 382, 402, 414, 431, 451, 477, 480, 500, 529, 533, 549, 578, 598, 623, 627, 647, 665, 676, 685, 696, 717, 725, 745, 774, 794, 822, 823, 843, 845, 872, 892, 902, 912, 921, 941
OFFSET
1,1
LINKS
FORMULA
{n: A008865(n) in A013929} . - R. J. Mathar, Sep 26 2013
MAPLE
remove(n -> numtheory:-issqrfree(n^2-2), [$1..1000]); # Robert Israel, Nov 03 2019
MATHEMATICA
Select[Range[1000], !SquareFreeQ[#^2-2]&] (* Harvey P. Dale, Jun 14 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Gerasimov Sergey, Aug 12 2013
EXTENSIONS
Corrected by R. J. Mathar, Sep 26 2013
STATUS
approved