A278722 Number of nX3 0..3 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order.

20, 275, 3232, 33466, 306070, 2487889, 18151220, 120104810, 727684612, 4070893254, 21181152380, 103146867706, 472709673984, 2048611972127, 8431440391174, 33079800818118, 124138709933301, 446936241587393

Offset: 1

Author

R. H. Hardin, Nov 27 2016

Keywords

• nonn

Comments

Column 3 of A278727.

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210
• R. H. Hardin, Empirical polynomial of degree 45

Crossrefs

Cf. A278727.

Formula

Empirical polynomial of degree 45 (see link above)