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 A075138 #3 Mar 30 2012 17:22:26
%S A075138 1,6,66,528,1232,16016,496496,4468464,183207024,4213761552,
%T A075138 71633946384,71633946384,4369670729424,4369670729424,310246621789104,
%U A075138 5894685813992976,53052172325936784,2281243410015281712
%N A075138 Denominator of the generalized harmonic number H(n,5,1).
%C A075138 The numerators are in A075137. See A075135 for more details.
%t A075138 a=5; b=1; maxN=20; s=0; Denominator[Table[s+=1/(a n + b), {n, 0, maxN-1}]]
%Y A075138 Cf. A075135, A075137.
%K A075138 easy,frac,nonn
%O A075138 1,2
%A A075138 _T. D. Noe_, Sep 04 2002