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 A144935 #3 Mar 31 2012 14:40:18
%S A144935 0,4,32,512,11232,323648,11616768,500984576,25275854848,1461945274368,
%T A144935 95418154739712,6939291871629312,556552095965593600,
%U A144935 48807623034247200768,4646562962112939622400,477275845583045903777792
%N A144935 Number of hyperforests with n labeled vertices when edges of size 1 are allowed (with no two equal edges), without isolated nodes nor isolated loops.
%D A144935 D. E. Knuth: The Art of Computer Programming, Volume 4, Generating All Combinations and Partitions Fascicle 3, Section 7.2.1.4. Generating all partitions. Page 38, Algorithm H.
%F A144935 a(n) = Sum of n!prod_{k=1}^n\{ frac{ A134958(k)^{c_k} }{ k!^{c_k} c_k! } } over all the partitions of n with parts k > 1, c_1 + 2c_2 + ... + nc_n; c_1, c_2, ..., c_n >= 0.
%e A144935 a(5) = 11232 since the partitions of 5 with parts > 1 are [5] and [3,2]. The partition [5] corresponds to 9952 hypergraphs and [3,2] corresponds to 5!4/2!32/3! = 1280.
%Y A144935 Cf. A134958(hypertrees), A134956(hyperforests).
%K A144935 nonn
%O A144935 1,2
%A A144935 _Washington Bomfim_, Sep 25 2008