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 A309227 #15 Jul 25 2019 10:06:51
%S A309227 1215571544,1270824975,1467511664,1512587175,1530808335,1579407344,
%T A309227 1638031815,1727239544
%N A309227 Quasi-sociable numbers.
%C A309227 The smallest quasi-sociable number cycle is {1215571544, 1270824975, 1467511664, 1530808335, 1579407344, 1638031815, 1727239544, 151258717, 1215571544}. They are the only known quasi-sociable numbers in 2019.
%C A309227 a(9) > 10^12, if it exists. - _Giovanni Resta_, Jul 25 2019
%H A309227 David Moews, <a href="http://djm.cc/redsoc.fmtlist">Reduced sociable numbers</a> (e-mailed by Mitchell Dickerman on Sep. 10, 1997).
%e A309227 1215571544 = 2^3 * 11 * 13813313
%e A309227 1270824975 = 3^2 * 5^2 * 7 * 19 * 42467
%e A309227 1467511664 = 2^4 * 19 * 599 * 8059
%e A309227 1530808335 = 3^3 * 5 * 7 * 1619903
%e A309227 1579407344 = 2^4 * 31^2 * 59 * 1741
%e A309227 1638031815 = 3^4 * 5 * 7 * 521 * 1109
%e A309227 1727239544 = 2^3 * 2671 * 80833
%e A309227 1512587175 = 3 * 5^2 * 11 * 1833439
%Y A309227 Cf. A122726 (sociable numbers), A005276 (betrothed (or quasi-amicable) numbers).
%K A309227 nonn,hard
%O A309227 1,1
%A A309227 _Donghwi Park_, Jul 16 2019