A185564 1/4 the number of nX6 0..3 arrays with no element equal both to the element above and to the element to its left.

1024, 3037500, 8977824540, 26533211918040, 78416544382742160, 231753101877188629380, 684925618712729136913980, 2024236566241727245692157080, 5982450596328307878990974438640

Offset: 1

Author

R. H. Hardin Jan 31 2011

Keywords

• nonn

Comments

Column 6 of A185567

Examples

			Some solutions for 3X6 with a(1,1)=0
..0..0..0..2..2..2....0..0..0..2..0..0....0..0..0..0..0..3....0..0..0..2..2..3
..0..2..2..0..1..0....0..2..0..2..2..1....0..2..2..2..0..2....0..2..0..2..0..3
..0..0..2..2..2..2....0..0..2..3..0..0....0..0..0..2..3..2....0..0..2..3..1..3
		

Links

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

Formula

Empirical: a(n)=3176*a(n-1)-673550*a(n-2)[phone]*a(n-3)-3727689126*a(n-4)[phone]*a(n-5)-3603160371660*a(n-6)[phone]*a(n-7)-810096692648238*a(n-8)+6824155175157060*a(n-9)-36345608355460626*a(n-10)+107463532615201134*a(n-11)-134880780658290660*a(n-12)+77768725332170250*a(n-13)-12154766339477250*a(n-14)-11593534218480000*a(n-15)+6932136333037500*a(n-16)-1023032228765625*a(n-17)