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 A075144 #3 Mar 30 2012 17:22:26
%S A075144 4,36,252,4788,9576,277704,4720968,61372584,675098424,4725688968,
%T A075144 14177066904,836446947336,6691575578688,153906238309824,
%U A075144 5694530817463488,449867934579615552,449867934579615552
%N A075144 Denominator of the generalized harmonic number H(n,5,4).
%C A075144 The numerators are in A075143. See A075135 for more details.
%t A075144 a=5; b=4; maxN=20; s=0; Denominator[Table[s+=1/(a n + b), {n, 0, maxN-1}]]
%Y A075144 Cf. A075135, A075143.
%K A075144 easy,frac,nonn
%O A075144 1,1
%A A075144 _T. D. Noe_, Sep 04 2002