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%I #20 Sep 08 2022 08:46:05
%S 3,7,10,11,15,19,21,22,23,27,28,30,31,33,34,35,39,43,46,47,48,51,55,
%T 57,58,59,63,66,67,69,70,71,75,77,79,82,83,84,87,91,92,93,94,95,99,
%U 102,103,105,106,107,110,111,112
%N Numbers k such that tau(2k) | sigma(2k).
%H Vincenzo Librandi, <a href="/A226934/b226934.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[ Range[120], Divisible[ DivisorSigma[1, 2*#], DivisorSigma[0, 2*#]] &] (* _Jean-François Alcover_, Jul 03 2013 *)
%o (PARI) is_a226394(n) = (sigma(2*n,1) % sigma(2*n,0) == 0) \\ _Michael B. Porter_, Jun 27 2013
%o (Magma) [n: n in [1..120] | IsZero(SumOfDivisors(2*n) mod NumberOfDivisors(2*n))]; // _Bruno Berselli_, Jun 28 2013
%Y Cf. A000005 (tau), A000203 (sigma), A003601, A049642.
%K nonn
%O 1,1
%A _Wesley Ivan Hurt_, Jun 22 2013
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