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 A046205 #12 Apr 05 2015 01:21:03 %S A046205 1,1,1,2,1,2,1,3,1,6,1,3,1,4,1,12,1,12,1,4,1,5,1,20,1,30,1,20,1,5,1,6, %T A046205 1,30,1,60,1,60,1,30,1,6,1,7,1,42,1,105,1,140,1,105,1,42,1,7,1,8,1,56, %U A046205 1,168,1,280,1,280,1,168,1,56,1,8,1,9,1,72,1,252,1,504,1,630,1,504,1 %N A046205 In Leibniz's Harmonic Triangle, write numerator first and then denominator of each element. %D A046205 L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 83, Problem 25. %e A046205 1/1; %e A046205 1/2, 1/2; %e A046205 1/3, 1/6, 1/3; %e A046205 1/4, 1/12, 1/12, 1/4; %e A046205 1/5, 1/20, 1/30, 1/20, 1/5; ... %Y A046205 Cf. A003506, A046206, A046212, A046201, A046204, A046208, A007622, A137752, A137753, A137754. %K A046205 tabf,nonn,easy,less %O A046205 1,4 %A A046205 _Mohammad K. Azarian_ %E A046205 More terms from Gregory D Johnson (gjohn(AT)iname.com) %E A046205 Edited by _M. F. Hasler_, Apr 05 2015