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 A140902 #7 Jan 17 2025 09:28:00
%S A140902 1,126,5292,116424,1646568,16818516,133613766,868489479,4789851066,
%T A140902 23029990984,98561919456,381644355456,1354627767168,4454641311264,
%U A140902 13691471089032,39620253756006,108618373687131,283595960194470,708397594804900,1699573176873000
%N A140902 Number of 4 X 5 matrices with elements in 0..n with each row and each column in nondecreasing order. 4,5,n can be permuted, see formula.
%H A140902 Feihu Liu, Guoce Xin, and Chen Zhang, <a href="https://arxiv.org/abs/2412.18744">Ehrhart Polynomials of Order Polytopes: Interpreting Combinatorial Sequences on the OEIS</a>, arXiv:2412.18744 [math.CO], 2024. See p. 25.
%F A140902 (empirical) set p,q,r to n,5,4 (in any order) in s=p+q+r-1; a(n) = product {i in 0..r-1} (binomial(s,p+i)*i!/(s-i)^(r-i-1))
%K A140902 nonn
%O A140902 0,2
%A A140902 _R. H. Hardin_, Jul 05 2008