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A223841 Number of 5 X n 0..1 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.

%I A223841 #7 Mar 18 2025 17:07:26
%S A223841 6,36,149,471,1240,2884,6159,12371,23716,43790,78342,136368,231677,
%T A223841 385101,627571,1004341,1580713,2449699,3742152,5640008,8393406,
%U A223841 12342594,17945687,25813519,36753026,51820812,72388786,100224016,137585227,187338675,253096459,339380689
%N A223841 Number of 5 X n 0..1 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing.
%H A223841 R. H. Hardin, <a href="/A223841/b223841.txt">Table of n, a(n) for n = 1..210</a>
%F A223841 Empirical: a(n) = (1/3628800)*n^10 - (1/241920)*n^9 + (17/120960)*n^8 - (1/13440)*n^7 + (3733/172800)*n^6 - (893/11520)*n^5 + (178931/90720)*n^4 - (188123/60480)*n^3 + (504149/25200)*n^2 - (30581/420)*n + 121 for n>4.
%e A223841 Some solutions for n=3:
%e A223841 ..0..0..0....0..0..0....0..0..0....1..1..0....0..1..0....0..0..0....0..0..0
%e A223841 ..0..0..1....0..0..0....0..0..0....1..1..0....1..1..0....0..1..0....0..0..0
%e A223841 ..0..1..1....1..0..0....0..1..0....1..1..0....1..1..0....1..1..0....0..1..0
%e A223841 ..0..1..1....1..0..0....0..1..0....1..1..0....1..1..0....1..1..1....0..1..0
%e A223841 ..0..1..1....1..1..0....1..1..1....1..1..1....1..1..0....1..1..1....1..1..0
%Y A223841 Row 5 of A223838.
%K A223841 nonn
%O A223841 1,1
%A A223841 _R. H. Hardin_, Mar 27 2013
%E A223841 Name corrected by _Andrew Howroyd_, Mar 18 2025