A240625 Number of nX2 0..3 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..3 introduced in row major order.

2, 10, 109, 1332, 16624, 208015, 2604059, 32601488, 408158709, 5110007540, 63975568178, 800952543871, 10027655890879, 125542872147582, 1571754448134085, 19677835970041564, 246359874423207164

Offset: 1

Author

R. H. Hardin, Apr 09 2014

Keywords

• nonn

Comments

Column 2 of A240629

Examples

			Some solutions for n=4
..0..1....0..1....0..1....0..0....0..1....0..1....0..1....0..1....0..0....0..1
..0..0....1..0....2..2....1..2....0..2....2..3....2..2....2..0....1..2....0..2
..0..2....2..1....0..1....3..2....1..0....3..1....1..1....1..3....2..1....3..0
..3..3....2..3....0..1....3..1....3..3....0..0....2..0....1..2....3..3....2..3
		

Links

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

Formula

Empirical: a(n) = 14*a(n-1) -14*a(n-2) -60*a(n-3) +29*a(n-4) +150*a(n-5) -47*a(n-6) -124*a(n-7) -4*a(n-8) +84*a(n-9) -27*a(n-10) for n>11