A222900 Number of nX2 0..3 arrays with no more than floor(nX2/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

1, 4, 14, 75, 411, 2522, 15919, 103627, 683480, 4554799, 30542304, 205785953, 1391485044, 9436529666, 64150640719, 437015936703, 2982527052975, 20387828050502, 139566607631735, 956650211233825, 6564964362464004

Offset: 1

Author

R. H. Hardin Mar 09 2013

Keywords

• nonn

Comments

Column 2 of A222906

Examples

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

Links

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