A212926 Number of n X 4 0..3 arrays with no column j greater than column j-1 in all rows.

35, 39695, 14177855, 4041974015, 1075113010175, 279128913678335, 71832238695530495, 18425105216039878655, 4720288982579567394815, 1208726373482189187710975, 309465862773085401709019135

Offset: 1

Author

R. H. Hardin, May 31 2012

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Column 4 of A212930.

Formula

Empirical: a(n) = 405*a(n-1) -43860*a(n-2) +1524160*a(n-3) -15636480*a(n-4) [phone]*a(n-5).

Empirical: a(n) = -3*96^n+256^n+36^n-1+2*16^n. - R. J. Mathar, Jun 27 2012