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 A156871 #12 Mar 12 2017 15:12:17 %S A156871 1,2,5,20,170,3650,298132,159632503 %N A156871 Number of nondecreasing sequences of n positive integers with reciprocals adding up to an integer. %F A156871 a(n) = A156869(n, 1) + ... + A156869(n, n). %e A156871 For n = 3, the A156871(3) = 5 sequences are (1, 1, 1), (1, 2, 2), (2, 3, 6), (2, 4, 4) and (3, 3, 3) because 1/1 + 1/1 + 1/1 = 3, 1/1 + 1/2 + 1/2 = 2 and 1/2 + 1/3 + 1/6 = 1/2 + 1/4 + 1/4 = 1/3 + 1/3 + 1/3 = 1. %Y A156871 Cf. A002966, A156869, A280517, A280518. %K A156871 more,nonn %O A156871 1,2 %A A156871 _Jens Voß_, Feb 17 2009 %E A156871 a(7), a(8) from _Max Alekseyev_, Jul 27 2009