A239813 Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it, modulo 4.

4, 23, 113, 582, 2981, 15266, 78188, 400542, 2051667, 10509067, 53831920, 275740995, 1412438656, 7234951864, 37059718148, 189831642853, 972377820507, 4980827553280, 25513377870835, 130687610786192, 669423377137934

Offset: 1

Author

R. H. Hardin, Mar 27 2014

Keywords

• nonn

Comments

Column 2 of A239819

Examples

			Some solutions for n=5
..2..0....2..0....2..0....3..2....3..2....3..0....3..0....3..2....2..3....2..0
..1..3....2..3....2..3....3..2....3..2....1..2....2..0....1..0....2..3....1..0
..3..2....3..1....3..1....2..3....1..0....2..0....1..3....3..2....2..0....3..0
..1..3....1..0....3..2....3..2....1..2....1..2....1..2....3..2....1..2....1..3
..2..3....3..0....1..2....1..3....2..0....1..0....1..3....2..1....2..0....1..3
		

Links

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

Formula

Empirical: a(n) = a(n-1) +16*a(n-2) +31*a(n-3) -8*a(n-4) -78*a(n-5) -45*a(n-6) +56*a(n-7) -32*a(n-8) +32*a(n-9) +16*a(n-10)