login
Number of 3Xn 0..1 arrays with row sums nondecreasing and column sums unimodal
1

%I #4 Mar 24 2013 10:29:39

%S 4,26,147,751,3560,15778,67030,274631,1088767,4218662,16015929,

%T 59653826,219063215,794078382,2843032061,10081383128,35429305737,

%U 123436612116,427070556002,1467917436855,5013326271265,17031672794426,57571509067410

%N Number of 3Xn 0..1 arrays with row sums nondecreasing and column sums unimodal

%C Row 3 of A223625

%H R. H. Hardin, <a href="/A223627/b223627.txt">Table of n, a(n) for n = 1..116</a>

%e Some solutions for n=3

%e ..0..1..0....0..0..1....0..1..0....1..0..0....0..0..1....0..0..0....0..0..1

%e ..0..1..0....1..1..0....1..0..0....0..1..0....0..1..0....0..0..0....1..1..1

%e ..1..0..0....1..1..1....1..0..0....0..0..1....0..0..1....0..0..1....1..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 24 2013