A209096 Number of n X 4 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

14, 520, 20928, 849548, 34538488, 1404480904, 57113932788, 2322577420320, 94449268074144, 3840847202693708, 156190807044264984, 6351611234890358120, 258292828185791666996, 10503663185141042925120, 427138999879594132134016

Offset: 1

Author

R. H. Hardin, Mar 05 2012

Keywords

• nonn

Comments

Column 4 of A209100.

Examples

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

Links

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

Crossrefs

Cf. A209100.

Formula

Empirical: a(n) = 49*a(n-1) - 356*a(n-2) + 705*a(n-3) - 425*a(n-4) + 64*a(n-5) for n>6.

Empirical g.f.: 2*x*(7 - 83*x + 216*x^2 - 337*x^3 + 177*x^4 - 28*x^5) / (1 - 49*x + 356*x^2 - 705*x^3 + 425*x^4 - 64*x^5). - Colin Barker, Jul 08 2018