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 A144320 #4 Mar 30 2012 17:37:28
%S A144320 1,1,64,4096,264160,16906240,1082257408,69264474112,4432942899904,
%T A144320 283708353851392,18157335711582208,1162069485541261312,
%U A144320 74372447143871647744,4759836617207785455616,304629543505661931028480
%N A144320 Shifts left when Dirichlet convolution (DC:(b,b)->a) applied 6 times.
%H A144320 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%p A144320 k:=6: with (numtheory): dc:= proc(b,c) proc(n) option remember; add (b(d) *c(n/d), d=`if`(n<0,{}, divisors(n))) end end: a:='a': b[1]:= dc(a,a): for t from 2 to k do b[t]:= dc(b[t-1], b[t-1]) od: a:= n-> `if`(n=1, 1, b[k](n-1)): seq (a(n), n=1..25);
%Y A144320 6th column of A144324.
%K A144320 eigen,nonn
%O A144320 1,3
%A A144320 _Alois P. Heinz_, Sep 17 2008