A208144 Number of 5Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

10, 100, 450, 2025, 6300, 19600, 49000, 122500, 264600, 571536, 1111320, 2160900, 3880800, 6969600, 11761200, 19847025, 31853250, 51122500, 78728650, 121242121, 180360180, 268304400, 387550800, 559795600, 788351200, 1110222400, 1529388000

Offset: 1

Author

R. H. Hardin Feb 23 2012

Keywords

• nonn

Comments

Row 5 of A208142

Examples

			Some solutions for n=4
..0..0..0..0....0..0..0..0....0..0..0..0....1..0..1..0....0..1..0..0
..1..0..0..0....1..1..0..0....0..1..0..1....1..1..1..1....0..0..0..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..1....0..0..0..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..0....0..0..0..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..1..0..0....0..0..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)