A208411 Number of 4 X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

15, 2795, 667478, 163422914, 40039156736, 9810325806914, 2403711876698218, 588954110860577394, 144304709913279198696, 35357337571782719886214, 8663205247528271356492160, 2122646395773319892200238358

Offset: 1

Author

R. H. Hardin, Feb 26 2012

Keywords

• nonn

Comments

Row 4 of A208408.

Examples

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

Links

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

Crossrefs

Cf. A208408.

Formula

Empirical: a(n) = 226*a(n-1) +4747*a(n-2) -18294*a(n-3) -739509*a(n-4) -1661510*a(n-5) [phone]*a(n-6) [phone]*a(n-7) -98711047*a(n-8) -11588022*a(n-9) [phone]*a(n-10) -44074854*a(n-11) -121060656*a(n-12) [phone]*a(n-13) -10077696*a(n-14) for n>16.