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 A343245 #15 Apr 09 2021 02:30:49
%S A343245 1,1,16,190051,48563893286,62416511444764621,278991478506233367981237,
%T A343245 3489283612532675861618129664796,
%U A343245 104930321415012656258005668476458298401,6780157485532072442175423032103032983044918034
%N A343245 Hyperplane-counting upper bound on the number of sorted orders of X+Y for two lists X and Y of length n.
%C A343245 Grows asymptotically as O(n^(8n)) (Fredman 1976).
%H A343245 Michael L. Fredman (1976). "<a href="https://doi.org/10.1016%2F0304-3975%2876%2990078-5">How good is the information theory bound in sorting?</a>". Theoretical Computer Science. 1 (4): 355-361.
%H A343245 Wikipedia, <a href="https://en.wikipedia.org/wiki/X_%2B_Y_sorting">X+Y sorting</a>.
%F A343245 a(n) = Sum_{i=0..2*n} binomial(2*binomial(n,2)^2 + 2*binomial(n,2), i).
%e A343245 For n=2, 2*binomial(n,2)^2 + 2*binomial(n,2) = 4 and binomial(4,0) + ... + binomial(4,2*n) = 16, so a(2)=16.
%K A343245 nonn
%O A343245 0,3
%A A343245 _David Eppstein_, Apr 08 2021