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A074627 Numbers n such that sigma(n) is divisible by 6. 10

%I

%S 5,6,10,11,14,15,17,20,22,23,24,26,29,30,33,34,35,38,40,41,42,44,45,

%T 46,47,51,53,54,55,56,58,59,60,62,65,66,68,69,70,71,74,77,78,80,82,83,

%U 85,86,87,88,89,90,92,94,95,96,99,101,102,104,105,106,107,110,113,114,115

%N Numbers n such that sigma(n) is divisible by 6.

%C n=10: sigma(10) = 1+2+5+10 = 18 = 3*6.

%H Michael De Vlieger, <a href="/A074627/b074627.txt">Table of n, a(n) for n = 1..10000</a>

%F A000203(n) modulo 6 = 0.

%F {n: A084301(n) = 0 }. - _R. J. Mathar_, May 19 2020

%F A087943 INTERSECT A028983. - _R. J. Mathar_, May 19 2020

%t Select[Range@ 120, Divisible[DivisorSigma[1, #], 6] &] (* _Michael De Vlieger_, Feb 25 2017 *)

%o (PARI) isok(n) = !(sigma(n) % 6); \\ _Michel Marcus_, Dec 17 2013

%Y Cf. A000203, A072862, A074384, A074628, A067051, A074630.

%K easy,nonn

%O 1,1

%A _Labos Elemer_, Aug 26 2002

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Last modified June 19 12:02 EDT 2021. Contains 345128 sequences. (Running on oeis4.)