A223826 Number of nX3 0..2 arrays with rows and columns unimodal.

22, 484, 6166, 51136, 310396, 1492552, 5995781, 20879061, 64727664, 182215264, 472897132, 1144905802, 2610251996, 5646952970, 11664925145, 23128319257, 44207709722, 81762385076, 146787187114, 256501341004, 437310109972

Offset: 1

Author

R. H. Hardin Mar 27 2013

Keywords

• nonn

Comments

Column 3 of A223831

Examples

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

Links

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

Formula

Empirical: a(n) = (5051/239500800)*n^12 + (17911/39916800)*n^11 + (113633/21772800)*n^10 + (27157/725760)*n^9 + (1331621/7257600)*n^8 + (36461/57600)*n^7 + (35192219/21772800)*n^6 + (2190431/725760)*n^5 + (24210049/5443200)*n^4 + (4187689/907200)*n^3 + (882989/207900)*n^2 + (2173/990)*n + 1