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A072462
Numbers k such that sigma(k) == 3 (mod 4).
6
2, 4, 8, 16, 18, 25, 32, 36, 64, 72, 98, 128, 144, 162, 169, 196, 225, 242, 256, 288, 289, 324, 392, 484, 512, 576, 648, 722, 784, 841, 882, 968, 1024, 1058, 1152, 1225, 1250, 1296, 1369, 1444, 1458, 1521, 1568, 1681, 1764, 1922, 1936, 2025, 2048, 2116, 2178
OFFSET
1,1
LINKS
MATHEMATICA
Select[Range[2200], Mod[DivisorSigma[1, #], 4] == 3 &] (* Michael De Vlieger, Aug 10 2023 *)
PROG
(PARI) isok(n) = ((sigma(n) % 4) == 3); \\ Michel Marcus, Dec 19 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jun 19 2002
EXTENSIONS
Name edited by Michel Marcus, Dec 19 2013
STATUS
approved