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A250688 Number of (n+1)X(5+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.

%I A250688 #6 Jul 23 2025 12:41:43
%S A250688 47002,249512,1315446,6671458,31728758,143136866,617657415,2571646112,
%T A250688 10412478449,41269021168,160968910027,620573782940,2373117015149,
%U A250688 9027885707796,34248252841075,129817387985168,492449247898701
%N A250688 Number of (n+1)X(5+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.
%C A250688 Column 5 of A250691
%H A250688 R. H. Hardin, <a href="/A250688/b250688.txt">Table of n, a(n) for n = 1..210</a>
%F A250688 Empirical: a(n) = 27*a(n-1) -331*a(n-2) +2439*a(n-3) -12049*a(n-4) +42129*a(n-5) -107225*a(n-6) +201069*a(n-7) -277706*a(n-8) +278928*a(n-9) -197984*a(n-10) +94032*a(n-11) -26784*a(n-12) +3456*a(n-13) for n>17
%e A250688 Some solutions for n=1
%e A250688 ..0..3..1..0..1..1....2..2..2..0..0..1....3..1..1..2..3..0....0..1..0..1..0..1
%e A250688 ..0..3..2..2..3..3....2..2..2..0..1..2....3..1..1..2..3..1....1..2..1..2..1..2
%K A250688 nonn
%O A250688 1,1
%A A250688 _R. H. Hardin_, Nov 26 2014