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 A144791 #14 Apr 07 2019 09:05:39 %S A144791 1,4,11,34,93,269,735,2037,5515,14912,39828,105931,279408,733409, %T A144791 1913349,4968092,12835746,33020764,84586922,215844162,548725545, %U A144791 1390140594,3510064528,8834980324,22171254453,55479601543,138448505906,344594242788,855538158016 %N A144791 Euler transform of A141199. %H A144791 Alois P. Heinz, <a href="/A144791/b144791.txt">Table of n, a(n) for n = 1..100</a> %H A144791 Thomas Wieder, <a href="http://www.m-hikari.com/ams/ams-password-2009/ams-password53-56-2009/wiederAMS53-56-2009.pdf">The number of certain rankings and hierarchies formed from labeled or unlabeled elements and sets</a>, Applied Mathematical Sciences, vol. 3, 2009, no. 55, 2707 - 2724. [_Thomas Wieder_, Nov 14 2009] %F A144791 G.f.: 1 / Product_{k>=1} (1 - x^k)^A141199(k). %F A144791 a(n) = (1/n)*Sum_{k=1..n-1} c(k) A141199(n-k), %F A144791 where c(n) = Sum_{k|n} k*A141199(k). %Y A144791 Cf. A141199, A144792, A144791. %K A144791 nonn %O A144791 1,2 %A A144791 _Thomas Wieder_, Sep 21 2008 %E A144791 More terms from _Alois P. Heinz_, Apr 21 2012