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A219501 Number of n X 7 arrays of the minimum value of corresponding elements and their horizontal or vertical neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 n X 7 array.

%I A219501 #5 Dec 26 2023 16:51:36
%S A219501 7,13,45,126,281,550,995,1703,2793,4424,6804,10200,14949,21470,30277,
%T A219501 41993,57365,77280,102782,135090,175617,225990,288071,363979,456113,
%U A219501 567176,700200,858572,1046061,1266846,1525545,1827245,2177533,2582528
%N A219501 Number of n X 7 arrays of the minimum value of corresponding elements and their horizontal or vertical neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 n X 7 array.
%C A219501 Column 7 of A219502.
%F A219501 Empirical: a(n) = (1/720)*n^6 + (1/240)*n^5 + (23/144)*n^4 + (13/16)*n^3 + (331/180)*n^2 + (311/60)*n - 27 for n>3.
%e A219501 Some solutions for n=3
%e A219501 ..0..0..0..0..0..0..0....1..0..0..0..0..0..0....1..0..0..0..0..0..0
%e A219501 ..1..0..0..0..0..0..0....1..1..0..0..0..0..0....1..1..0..0..0..0..0
%e A219501 ..1..1..1..1..1..1..0....1..1..1..1..1..1..0....1..1..1..1..0..0..0
%Y A219501 Cf. A219502.
%K A219501 nonn
%O A219501 1,1
%A A219501 _R. H. Hardin_, Nov 20 2012