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 A137764 #8 Jun 22 2013 16:06:10 %S A137764 2,1,3,1,12,7,4,1,20,9,5,1,60,49,30,11,6,1,105,71,42,13,7,1,280,351, %T A137764 168,97,56,15,8,1,504,545,252,127,72,17,9,1,1260,2561,840,799,360,161, %U A137764 90,19,10,1,2310,4159,1320,1121,495,199,110,21,11,1 %N A137764 Elements to the right of the central elements in writing first the denominator and then the numerator(left to right) of Leibniz's harmonic-like triangle. %e A137764 1/1; --> %e A137764 1/2, 1/2; --> 2 1 %e A137764 1/3, 5/6, 1/3; --> 3 1 %e A137764 1/4, 7/12, 7/12, 1/4; --> ... %e A137764 1/5, 9/20, 31/30, 9/20, 1/5; %Y A137764 Cf. A046201; A046204; A046205; A046206; A046208; A046212; A137752; A137753; A137754; A137755; A137756; A137757; A137758; A137759, A137760; A137761; A137762; A137763. %K A137764 nonn,tabf,frac,less %O A137764 1,1 %A A137764 _Mohammad K. Azarian_, Feb 13 2008