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 A073823 #5 Sep 25 2012 11:22:48 %S A073823 7,5,9,8,4,3,5,4,3,0,6,2,0,6,1,4,7,0,1,0,5,2,7,7,8,4,1,7,9,1,8,0,9,7, %T A073823 0,8,8,6,4,6,8,0,2,4,3,8,5,1,7,2,6,1,5,8,1,7,8,5,9,8,8,5,2,3,0,4,3,0, %U A073823 9,9,4,2,0,2,9,8,1,2,4,7,1,8,8,3,5,5,6,1,4,5,9,6,1,4,7,9,1,9,4,0,0,1,3,5 %N A073823 Decimal expansion of number with continued fraction expansion 0, 1, 3, 6, 10, ... (the triangular numbers). %e A073823 0.75984354306206147010527784179... %t A073823 RealDigits[FromContinuedFraction[Accumulate[Range[0,200]]],10,120] [[1]] (* _Harvey P. Dale_, Sep 25 2012 *) %o A073823 (PARI) dec_exp(v)= w=contfracpnqn(v); w[1,1]/w[2,1]+0. dec_exp(vector(2000,i,i*(i-1)/2)) %Y A073823 Cf. A000217 (triangular numbers). %K A073823 cons,nonn %O A073823 0,1 %A A073823 _Rick L. Shepherd_, Aug 12 2002