A229375 Number of nX3 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally.

22, 126, 956, 6730, 48490, 346598, 2486980, 17808604, 127696504, 914844004, 6558227280, 46993954326, 336844120550, 2413933454878, 17301596035866, 123994418056868, 888689321106698, 6369062557713410, 45647482408072212

Offset: 1

Author

R. H. Hardin Sep 21 2013

Keywords

• nonn

Comments

Column 3 of A229380

Examples

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

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +50*a(n-2) -133*a(n-3) -653*a(n-4) +1214*a(n-5) +2281*a(n-6) -3420*a(n-7) -2248*a(n-8) +2704*a(n-9) +835*a(n-10) -481*a(n-11) -120*a(n-12)