A224305 Number of n X 3 0..2 arrays with diagonals and rows unimodal and antidiagonals nondecreasing.

22, 218, 1586, 11361, 82700, 615481, 4634768, 35003328, 264487714, 1997888432, 15087449584, 113921725004, 860155842566, 6494472790364, 49035576285772, 370236844834368, 2795429838028120, 21106576528056696, 159362840727871756

Offset: 1

Author

R. H. Hardin Apr 03 2013

Keywords

• nonn

Comments

Column 3 of A224310.

Examples

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

Links

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

Crossrefs

Cf. A224310.

Formula

Empirical: a(n) = 10*a(n-1) -16*a(n-2) -24*a(n-3) -44*a(n-4) +728*a(n-5) -678*a(n-6) -722*a(n-7) -860*a(n-8) +9336*a(n-9) -3916*a(n-10) +792*a(n-11) +320*a(n-12) -11936*a(n-13) +2848*a(n-14) +128*a(n-15) +384*a(n-16) +3840*a(n-17).