A228279 Number of n X 4 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.

3, 6, 35, 133, 587, 2448, 10414, 44024, 186414, 789100, 3340345, 14140347, 59858152, 253389483, 1072638232, 4540650778, 19221306410, 81366888278, 344439152622, 1458066449898, 6172230293325, 26128045670722, 110604228640954

Offset: 1

Author

R. H. Hardin, Aug 19 2013

Keywords

• nonn

Comments

Column 4 of A228285.

Examples

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

Links

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

Crossrefs

See A228277-A228285, especially the latter.

Formula

a(n) = a(n-1) + 10*a(n-2) + 15*a(n-3) + 4*a(n-4) - 6*a(n-5) - a(n-6) + 3*a(n-7) - a(n-8).

G.f.: x*(1 - x)*(3 + 6*x + 5*x^2 - 2*x^3) / (1 - x - 10*x^2 - 15*x^3 - 4*x^4 + 6*x^5 + x^6 - 3*x^7 + x^8). - Colin Barker, Mar 16 2018

Extensions

Edited by N. J. A. Sloane, Aug 22 2013