A228140 Numbers n such that n^2 - 2 is not squarefree.

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

Author

Gerasimov Sergey, Aug 12 2013

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A005117, A008865, A013929, A173186.

Programs

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 *)

Formula

{n: A008865(n) in A013929} . - R. J. Mathar, Sep 26 2013

Extensions

Corrected by R. J. Mathar, Sep 26 2013