A240627 Number of nX4 0..3 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..3 introduced in row major order.

12, 1332, 180480, 24648700, 3367163455, 459961775083, 62832360051504, 8583108386132548, 1172481146489555199, 160164822767286567296, 21879047288760831684789, 2988750601081901561336772

Offset: 1

Author

R. H. Hardin, Apr 09 2014

Keywords

• nonn

Comments

Column 4 of A240629

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..178