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A250909 Number of (n+1)X(4+1) 0..2 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element.

%I A250909 #6 Jul 23 2025 12:50:38
%S A250909 39960,6621219,1096982379,181725094746,30104106257115,
%T A250909 4986961280614953,826125782084148708,136853637633971644347,
%U A250909 22670782687226177355267,3755577099313037361116844,622138174177304855831638383
%N A250909 Number of (n+1)X(4+1) 0..2 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element.
%C A250909 Column 4 of A250913
%H A250909 R. H. Hardin, <a href="/A250909/b250909.txt">Table of n, a(n) for n = 1..210</a>
%F A250909 Empirical: a(n) = 202*a(n-1) -6346*a(n-2) +54499*a(n-3) -108047*a(n-4) +2308813*a(n-5) -8304217*a(n-6) -16011215*a(n-7) +3358369*a(n-8) +18927043*a(n-9) -60255820*a(n-10) +18024160*a(n-11) +47390528*a(n-12) -6773760*a(n-13)
%e A250909 Some solutions for n=1
%e A250909 ..1..1..2..2..0....1..2..2..1..2....2..0..2..2..2....2..1..2..0..0
%e A250909 ..1..0..0..0..1....1..2..1..1..2....1..0..1..1..2....2..1..0..0..2
%K A250909 nonn
%O A250909 1,1
%A A250909 _R. H. Hardin_, Nov 28 2014