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%I #19 Sep 08 2022 08:46:09
%S 58,59,157,284,338,373,382,500,598,725,745,823,843,941,1039,1111,1166,
%T 1201,1264,1382,1400,1480,1490,1607,1705,1732,1823,1921,1999,2038,
%U 2048,2146,2264,2272,2362,2489,2587,2686,2705,2767,2803,2930,3028,3146,3244,3371,3469,3547,3587,3685,3712
%N Numbers n such that (n^2 - 2) and (n^2 + 2) are not squarefree.
%C Intersection of A227897 and A228140.
%C Primes: 59, 157, 373, 823, 941, 1039, 1201, 1607, 1823, 1999, 2767, 2803, 3371, 3469, 3547, ...
%H Colin Barker, <a href="/A247096/b247096.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[4000],! SquareFreeQ[#^2 - 2] && ! SquareFreeQ[#^2 + 2] &] (* _Vincenzo Librandi_, Nov 18 2014 *)
%o (Magma) [n: n in [1..4000] | not IsSquarefree(n^2 - 2) and not IsSquarefree(n^2 + 2)];
%o (PARI) select(n->!issquarefree(n^2-2) && !issquarefree(n^2+2), vector(4000, n, n)) \\ _Colin Barker_, Nov 18 2014
%Y Cf. A227897, A228140.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Nov 18 2014
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