A189336 Number of nX2 binary arrays without the pattern 1 0 0 1 diagonally, vertically, antidiagonally or horizontally.

4, 16, 64, 225, 784, 2704, 9409, 32761, 114244, 398161, 1387684, 4835601, 16851025, 58721569, 204633025, 713103616, 2485022500, 8659791364, 30177596089, 105162706944, 366470415424, 1277074025929, 4450340433889, 15508521343396

Offset: 1

Author

R. H. Hardin Apr 20 2011

Keywords

• nonn

Comments

Column 2 of A189343

Examples

			Some solutions for 4X2
..0..0....1..0....1..0....0..0....1..0....0..1....0..0....0..1....1..1....0..0
..1..1....1..0....0..0....1..0....1..0....0..1....1..1....1..0....0..1....1..1
..0..0....1..0....1..0....0..1....0..1....0..1....1..0....0..1....1..0....1..1
..0..1....0..1....1..1....0..1....1..1....0..0....0..1....1..0....0..1....1..1
		

Links

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

Crossrefs

A049864(n+2) squared

Formula

Empirical: a(n) = 4*a(n-1) -a(n-2) -6*a(n-3) +12*a(n-4) -3*a(n-5) +3*a(n-6) -6*a(n-7) +a(n-8) -a(n-9) +a(n-10)