A205189 Number of (n+1) X 5 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock differing from each horizontal or vertical neighbor.

72, 104, 160, 256, 384, 576, 864, 1312, 1984, 3008, 4544, 6880, 10400, 15744, 23808, 36032, 54496, 82464, 124736, 188736, 285504, 431968, 653472, 988672, 1495680, 2262848, 3423328, 5179168, 7835328, 11854016, 17933504, 27131360, 41046176

Offset: 1

Author

R. H. Hardin, Jan 23 2012

Keywords

• nonn

Comments

Column 4 of A205193.

Examples

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

Links

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

Crossrefs

Cf. A205193.

Formula

Empirical: a(n) = a(n-1) +a(n-2) -a(n-3) +a(n-4) for n>6.

Empirical g.f.: 8*x*(9 + 4*x - 2*x^2 + 8*x^3 - x^5) / (1 - x - x^2 + x^3 - x^4). - Colin Barker, Jun 11 2018