A203377 Number of (n+1)X8 0..1 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements.

8748, 323852, 12301020, 471988172, 18189909480, 702420750924, 27149753088792, 1049837466171436, 40603753889665632, 1570549319417597656, 60751409051086135560, 2350012855527394133452, 90905131505907584858388

Offset: 1

Author

R. H. Hardin Dec 31 2011

Keywords

• nonn

Comments

Column 7 of A203378

Examples

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

Links

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

Formula

Empirical: a(n) = 105*a(n-1) -4473*a(n-2) +105654*a(n-3) -1580037*a(n-4) [phone]*a(n-5) -116408090*a(n-6) [phone]*a(n-7) -2425718097*a(n-8) [phone]*a(n-9) -16063429749*a(n-10) [phone]*a(n-11) -34525830041*a(n-12) [phone]*a(n-13) -22785383754*a(n-14) [phone]*a(n-15) -3932260752*a(n-16) [phone]*a(n-17) -115250048*a(n-18) +6527616*a(n-19)