A209228 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.

28, 784, 896, 1024, 3456, 11664, 38232, 125316, 423384, 1430416, 4755296, 15808576, 53167072, 178810384, 596712128, 1991301376, 6681462272, 22418473984, 74937067264, 250488238144, 839514567296, 2813643921664, 9412504049664

Offset: 1

Author

R. H. Hardin Mar 06 2012

Keywords

• nonn

Comments

Row 7 of A209224

Examples

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

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +6*a(n-3) +84*a(n-4) -128*a(n-5) -44*a(n-6) -144*a(n-7) -1872*a(n-8) +2504*a(n-9) +864*a(n-10) +1088*a(n-11) +16128*a(n-12) -19968*a(n-13) -5632*a(n-14) -2816*a(n-15) -57344*a(n-16) +66560*a(n-17) +11264*a(n-18) +4096*a(n-19) +77824*a(n-20) -83968*a(n-21) -8192*a(n-22) -32768*a(n-24) +32768*a(n-25) for n>28