A205021 Number of (n+1)X3 0..3 arrays with the determinants of 2X2 subblocks nondecreasing rightwards and downwards

2338, 27611, 275853, 3684581, 56088455, 888172440, 14267356381, 230651852383, 3739445935138, 60705486742742, 986065323772866, 16021434746669572, 260345712140671916, 4230813125922375591, 68755635262011437219

Offset

1,1

Comments

Column 2 of A205027

Links

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

Formula

Empirical: a(n) = 24*a(n-1) -102*a(n-2) -656*a(n-3) +4911*a(n-4) -9576*a(n-5) +5400*a(n-6) for n>21

Example

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

Crossrefs

Sequence in context: A166581 A237387 A212466 * A207296 A043440 A023938

Adjacent sequences: A205018 A205019 A205020 * A205022 A205023 A205024

Keyword

nonn

Author

R. H. Hardin Jan 21 2012

Status

approved