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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.

A223776 Number of nX7 0..1 arrays with rows and columns unimodal and antidiagonals nondecreasing.

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%I A223776 #6 Jul 23 2025 04:30:02
%S A223776 29,267,1269,4246,11635,28346,64256,138913,290180,589799,1170809,
%T A223776 2274787,4331570,8091182,14838137,26733456,47351379,82508140,
%U A223776 141522193,239102564,398139077,653770622,1059242178,1694236163,2676588670,4178587937
%N A223776 Number of nX7 0..1 arrays with rows and columns unimodal and antidiagonals nondecreasing.
%C A223776 Column 7 of A223777
%H A223776 R. H. Hardin, <a href="/A223776/b223776.txt">Table of n, a(n) for n = 1..210</a>
%F A223776 Empirical: a(n) = (1/87178291200)*n^14 + (1/4151347200)*n^13 + (1/106444800)*n^12 + (53/319334400)*n^11 + (409/87091200)*n^10 + (1681/29030400)*n^9 + (862999/609638400)*n^8 - (56411/29030400)*n^7 + (3673639/14515200)*n^6 - (4250857/7257600)*n^5 + (1960444733/119750400)*n^4 - (326164913/4989600)*n^3 + (89807927381/151351200)*n^2 - (113103797/51480)*n + 3030 for n>4
%e A223776 Some solutions for n=3
%e A223776 ..0..1..0..0..0..0..0....0..0..0..0..1..1..0....0..0..0..0..0..0..0
%e A223776 ..1..1..1..1..1..1..0....0..0..0..1..1..1..0....0..0..0..0..1..1..1
%e A223776 ..1..1..1..1..1..1..0....0..0..1..1..1..1..1....1..1..1..1..1..1..1
%K A223776 nonn
%O A223776 1,1
%A A223776 _R. H. Hardin_ Mar 27 2013