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 A224054 #6 Jul 23 2025 04:58:19 %S A224054 86,1915,18502,115716,568107,2392915,9064541,31777144,104876598, %T A224054 329032264,986501800,2835296957,7828424002,20803012406,53300631267, %U A224054 131909615889,315895583635,733342224413,1653158389976,3624784596348 %N A224054 Number of nX5 0..2 arrays with rows and columns unimodal and antidiagonals nondecreasing. %C A224054 Column 5 of A224057 %H A224054 R. H. Hardin, <a href="/A224054/b224054.txt">Table of n, a(n) for n = 1..210</a> %F A224054 Empirical: a(n) = (1/1379196149760000)*n^20 + (1/27583922995200)*n^19 + (67/43553562624000)*n^18 + (163/3908653056000)*n^17 + (33853/34871316480000)*n^16 + (190111/10461394944000)*n^15 + (2078491/6974263296000)*n^14 + (221821/55351296000)*n^13 + (343209919/6897623040000)*n^12 + (12543727/32845824000)*n^11 + (5532659291/1072963584000)*n^10 + (47191439329/1609445376000)*n^9 + (4217033948263/13076743680000)*n^8 + (559137652921/373621248000)*n^7 + (8858390764133/1120863744000)*n^6 + (3120341453/532224000)*n^5 + (759212883816859/9262693440000)*n^4 - (58527804403451/154378224000)*n^3 + (36684493649747/24443218800)*n^2 + (34656538003/23279256)*n - 11297 for n>5 %e A224054 Some solutions for n=3 %e A224054 ..0..0..0..2..1....0..0..1..1..0....0..1..1..0..0....0..1..0..0..0 %e A224054 ..2..2..2..2..1....1..2..1..1..0....2..1..1..0..0....1..1..2..0..0 %e A224054 ..2..2..2..1..1....2..2..2..1..0....1..2..2..2..0....1..2..2..0..0 %K A224054 nonn %O A224054 1,1 %A A224054 _R. H. Hardin_ Mar 30 2013