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%I #14 Aug 11 2023 09:59:55
%S 2,4,8,16,18,25,32,36,64,72,98,128,144,162,169,196,225,242,256,288,
%T 289,324,392,484,512,576,648,722,784,841,882,968,1024,1058,1152,1225,
%U 1250,1296,1369,1444,1458,1521,1568,1681,1764,1922,1936,2025,2048,2116,2178
%N Numbers k such that sigma(k) == 3 (mod 4).
%H Ray Chandler, <a href="/A072462/b072462.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[2200], Mod[DivisorSigma[1, #], 4] == 3 &] (* _Michael De Vlieger_, Aug 10 2023 *)
%o (PARI) isok(n) = ((sigma(n) % 4) == 3); \\ _Michel Marcus_, Dec 19 2013
%Y Cf. A000203, A028982, A072461.
%K nonn
%O 1,1
%A _Labos Elemer_, Jun 19 2002
%E Name edited by _Michel Marcus_, Dec 19 2013
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