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 A059819 #23 Jan 11 2022 10:51:58
%S A059819 0,1,3,5,9,11,18,19,28,30,40,39,57,51,68,68,86,77,107,91,123,114,138,
%T A059819 121,172,140,178,166,205,171,240,189,251,224,266,230,322,245,314,286,
%U A059819 356,283,396,303,403,361,416,343,497,368,479,424,515,407
%N A059819 Expansion of series related to Liouville's Last Theorem: g.f. Sum_{t>0} (-1)^(t+1) *x^(t*(t+1)/2) / ( (1-x^t)^2 *Product_{i=1..t} (1-x^i) ).
%H A059819 Seiichi Manyama, <a href="/A059819/b059819.txt">Table of n, a(n) for n = 0..10000</a>
%H A059819 G. E. Andrews, <a href="http://www.mat.univie.ac.at/~slc/s/s42andrews.html">Some debts I owe</a>, Séminaire Lotharingien de Combinatoire, Paper B42a, Issue 42, 2000; see (7.4).
%F A059819 a(n) = (sigma(n)+tau(n)+Sum_{k=0..n} tau(k)*tau(n-k))/2.
%F A059819 G.f.: (F(x)+G(x)^2)/2, where F(x) = Sum_{k>0} (k+1)*x^k/(1-x^k) and G(x) = Sum_{k>0} x^k/(1-x^k). - _Vladeta Jovovic_, Feb 12 2004
%p A059819 Mk := proc(k) -1*add( (-1)^n*q^(n*(n+1)/2)/(1-q^n)^k/mul(1-q^i,i=1..n), n=1..101): end; # with k=2
%Y A059819 Cf. A000005 (k=1), here (k=2), A059820 (k=3), ..., A059825 (k=8).
%Y A059819 Cf. A000203, A055507.
%K A059819 nonn
%O A059819 0,3
%A A059819 _N. J. A. Sloane_, Feb 24 2001