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A250657 Number of (3+1)X(n+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.

%I A250657 #6 Jul 23 2025 12:39:41
%S A250657 39,70,109,156,211,274,345,424,511,606,709,820,939,1066,1201,1344,
%T A250657 1495,1654,1821,1996,2179,2370,2569,2776,2991,3214,3445,3684,3931,
%U A250657 4186,4449,4720,4999,5286,5581,5884,6195,6514,6841,7176,7519,7870,8229,8596,8971
%N A250657 Number of (3+1)X(n+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.
%C A250657 Row 3 of A250656
%H A250657 R. H. Hardin, <a href="/A250657/b250657.txt">Table of n, a(n) for n = 1..210</a>
%F A250657 Empirical: a(n) = 4*n^2 + 19*n + 16
%e A250657 Some solutions for n=4
%e A250657 ..1..0..0..0..0....1..0..0..0..0....1..1..1..1..1....1..0..0..0..0
%e A250657 ..0..0..0..0..0....0..0..0..0..0....1..1..1..1..1....0..0..0..0..0
%e A250657 ..0..0..0..0..0....1..1..1..1..1....0..0..0..0..1....1..1..1..1..1
%e A250657 ..0..1..1..1..1....0..1..1..1..1....0..0..0..0..1....1..1..1..1..1
%K A250657 nonn
%O A250657 1,1
%A A250657 _R. H. Hardin_, Nov 26 2014