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%I #13 Mar 09 2023 15:34:25
%S 14,42,70,78,84,98,112,114,124,126,154,156,168,182,186,198,210,222,
%T 228,234,238,252,258,266,294,308,310,312,322,336,342,350,366,372,378,
%U 390,396,402,406,418,420,434,438,444,456,462,468,474,490,504,516,518,532,546,550,558
%N Even numbers k such that k^2 is not in A014567; complement of A356448 in the even numbers.
%C Even numbers k such that k and sigma(k^2) are not coprime, sigma = A000203.
%H Jianing Song, <a href="/A356452/b356452.txt">Table of n, a(n) for n = 1..12241</a> (all terms <= 80000)
%F a(n) = 2*A356454(n).
%e 14 is a term since 14 and sigma(14^2) = 399 have a common factor 7.
%t Select[2 Range[300],!CoprimeQ[#,DivisorSigma[1,#^2]]&] (* _Harvey P. Dale_, Mar 09 2023 *)
%o (PARI) isA356452(n) = !(n%2) && gcd(n, sigma(n^2))>1
%Y Cf. A014567, A000203, A356448, A356453, A356454.
%K nonn,easy
%O 1,1
%A _Jianing Song_, Aug 07 2022
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