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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.

A223636 Number of nX7 0..1 arrays with rows, antidiagonals and columns unimodal.

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%I A223636 #6 Jul 23 2025 04:19:14
%S A223636 29,841,12657,114713,748950,3907140,17224974,66448428,229624238,
%T A223636 723456027,2106393383,5727793388,14669871333,35633091730,82556882471,
%U A223636 183320486518,391738700030,808400385799,1615892668057,3136875572418
%N A223636 Number of nX7 0..1 arrays with rows, antidiagonals and columns unimodal.
%C A223636 Column 7 of A223637
%H A223636 R. H. Hardin, <a href="/A223636/b223636.txt">Table of n, a(n) for n = 1..201</a>
%F A223636 Empirical: a(n) = (503/209563200)*n^14 - (76217/778377600)*n^13 + (88483/23950080)*n^12 - (1160261/17107200)*n^11 + (158917/435456)*n^10 + (88785757/3628800)*n^9 - (2720678887/3048192)*n^8 + (182706654569/10886400)*n^7 - (2182833462133/10886400)*n^6 + (2369225181061/1555200)*n^5 - (18729229340021/2993760)*n^4 + (2512793025389/9979200)*n^3 + (795324348531341/5821200)*n^2 - (56828168983661/90090)*n + 981755694 for n>12
%e A223636 Some solutions for n=4
%e A223636 ..0..1..1..1..0..0..0....0..0..0..0..0..0..0....0..0..0..1..0..0..0
%e A223636 ..1..1..1..1..1..1..0....1..0..0..0..0..0..0....0..0..1..1..1..1..0
%e A223636 ..1..0..0..0..0..0..0....0..0..1..1..1..0..0....0..0..1..1..1..0..0
%e A223636 ..0..0..0..0..0..0..0....0..0..1..1..0..0..0....0..0..0..0..1..0..0
%K A223636 nonn
%O A223636 1,1
%A A223636 _R. H. Hardin_ Mar 24 2013