A185565 1/4 the number of nX7 0..3 arrays with no element equal both to the element above and to the element to its left.

4096, 45562500, 504547256880, 5586628402633500, 61858104930689319360, 684925618712729136913980, 7583858300260627032845531520, 83972485690826213759616527499540, 929787724653148422947168982361958940

Offset: 1

Author

R. H. Hardin Jan 31 2011

Keywords

• nonn

Comments

Column 7 of A185567

Examples

			Some solutions for 3X7 with a(1,1)=0
..0..0..0..0..0..0..1....0..0..0..0..1..1..2....0..0..0..0..2..0..2
..0..2..0..2..2..1..3....0..2..0..2..0..0..2....0..2..0..2..1..0..2
..0..0..2..0..0..1..3....0..0..2..0..1..0..3....0..0..2..0..1..3..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200