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 A193375 #11 Apr 29 2022 19:26:35
%S A193375 1,1,1,7,25,61,1201,7771,30577,514585,8089921,63701551,832599241,
%T A193375 14055894997,137066892145,3084240161731,70859008063201,
%U A193375 849408115312561,15997591979202817,358582896987674455,6017079190150763641,209473179919282488301
%N A193375 E.g.f.: A(x) = exp( Sum_{n>=1} x^(n*(n+1)/2) ).
%H A193375 Seiichi Manyama, <a href="/A193375/b193375.txt">Table of n, a(n) for n = 0..448</a>
%e A193375 E.g.f.: A(x) = 1 + x + x^2/2! + 7*x^3/3! + 25*x^4/4! + 61*x^5/5! +...
%e A193375 where
%e A193375 log(A(x)) = x + x^3 + x^6 + x^10 + x^15 + x^21 +...
%o A193375 (PARI) {a(n)=n!*polcoeff(exp(sum(m=1,sqrtint(2*n+1),x^(m*(m+1)/2)+x*O(x^n))),n)}
%Y A193375 Cf. A010054, A193374, A205800.
%K A193375 nonn
%O A193375 0,4
%A A193375 _Paul D. Hanna_, Jul 24 2011