This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A194771 #16 May 30 2020 04:12:15
%S A194771 2,12,56,240,992,1344,16256,60480,65520,1047552,4357080,47139840,
%T A194771 67100672,91065600,285981696,919636480,2758909440,2952609792,
%U A194771 17179738112,28364878080,63996791040,87722956800,102002360320,132867440640,137438691328
%N A194771 Even numbers that divide the sum of their even divisors.
%C A194771 Since the sum of even divisors of an odd number is zero, every odd number divides its sum of even divisors. - _Nathaniel Johnston_, Sep 02 2011
%F A194771 a(n) = 2*A007691(n).
%e A194771 The divisors of 56 are { 1, 2, 4, 7, 8, 14, 28, 56 } and the sum of the even divisors is 2 + 4 + 8 + 14 + 28 + 56 = 112, hence 56 divides 112, so 56 is in the sequence.
%p A194771 with(numtheory):for n from 1 to 10000000 do if(sigma(n) mod n = 0)then print(2*n):fi:od:
%Y A194771 Cf. A146076.
%K A194771 nonn
%O A194771 1,1
%A A194771 _Michel Lagneau_, Sep 02 2011
%E A194771 a(11)-a(25) from _Nathaniel Johnston_, Sep 02 2011