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 A019287 #38 Feb 27 2020 04:34:42 %S A019287 480,504,13824,32256,32736,1980342,1396617984,3258775296,14763499520, %T A019287 38385098752 %N A019287 Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,10)-perfect numbers. %C A019287 See also the Cohen-te Riele links under A019276. %C A019287 No other terms < 5*10^11. - _Jud McCranie_, Feb 08 2012 %C A019287 a(11) > 4*10^12, if it exists. - _Giovanni Resta_, Feb 26 2020 %H A019287 G. L. Cohen and H. J. J. te Riele, <a href="http://projecteuclid.org/euclid.em/1047565640">Iterating the sum-of-divisors function</a>, Experimental Mathematics, 5 (1996), pp. 93-100. %Y A019287 Cf. A019278, A019279, A019281, A019282, A019283, A019284, A019285, A019286, A019288, A019289, A019290, A019291. %K A019287 nonn,more %O A019287 1,1 %A A019287 _N. J. A. Sloane_ %E A019287 More terms from _Jud McCranie_, Nov 13 2001; a(9) Jan 29 2012, a(10) Feb 08 2012