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A223842 Number of 6 X n 0..1 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.

%I A223842 #9 Mar 18 2025 17:04:14
%S A223842 7,49,232,824,2388,5992,13582,28642,57306,110164,205131,371923,658926,
%T A223842 1143584,1947904,3261320,5374024,8725020,13970658,22081342,34476575,
%U A223842 53211615,81232894,122724138,183570978,271978936,399288201,581038793,838351784,1199706462,1703209968
%N A223842 Number of 6 X n 0..1 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.
%H A223842 R. H. Hardin, <a href="/A223842/b223842.txt">Table of n, a(n) for n = 1..210</a>
%F A223842 Empirical: a(n) = (1/479001600)*n^12 - (1/15966720)*n^11 + (13/6220800)*n^10 - (1/53760)*n^9 + (6631/14515200)*n^8 + (125/96768)*n^7 - (1017767/43545600)*n^6 + (1429367/1451520)*n^5 - (7479853/1555200)*n^4 + (4300223/120960)*n^3 - (151629803/1663200)*n^2 - (12136/231)*n + 528 for n>6.
%e A223842 Some solutions for n=3:
%e A223842 ..0..1..0....0..0..0....0..0..0....0..0..0....1..1..0....0..0..0....0..0..0
%e A223842 ..0..1..0....1..0..0....0..0..0....0..0..0....1..1..0....0..0..0....0..0..0
%e A223842 ..0..1..0....1..0..0....0..0..1....0..0..0....1..1..0....0..1..0....0..0..0
%e A223842 ..0..1..0....1..1..0....0..1..1....0..0..0....1..1..0....0..1..1....1..0..0
%e A223842 ..0..1..0....1..1..1....1..1..1....0..0..0....1..1..1....1..1..1....1..1..0
%e A223842 ..1..1..0....1..1..1....1..1..1....0..1..1....1..1..1....1..1..1....1..1..1
%Y A223842 Row 6 of A223838.
%K A223842 nonn
%O A223842 1,1
%A A223842 _R. H. Hardin_, Mar 27 2013
%E A223842 Name corrected by _Andrew Howroyd_, Mar 18 2025