A222909 Number of 4Xn 0..3 arrays with no more than floor(4Xn/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

15, 75, 767, 7794, 101398, 1346067, 21064292, 356150811, 6366063573, 115668702638, 2139261596454, 39572902785373, 737955955427551, 13730713590038976, 256798310856319397, 4793531311138014167

Offset: 1

Author

R. H. Hardin Mar 09 2013

Keywords

• nonn

Comments

Row 4 of A222906

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..31