A201273 Number of n X 4 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

1, 3, 12, 14, 85, 199, 143, 740, 1274, 759, 3416, 5312, 2746, 11628, 16676, 7946, 32164, 43438, 19713, 76321, 99347, 43137, 162566, 205231, 86351, 318364, 391600, 161089, 581578, 702330, 282904, 1006014, 1195239, 473473, 1662549, 1947164, 761467, 2641053, 3058967

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..10000 (terms n = 1..192 from R. H. Hardin)

Formula

a(n) = a(n-3) +2*a(n-6) +a(n-9) -4*a(n-12) -5*a(n-15) +4*a(n-18) +5*a(n-21) +a(n-24) -6*a(n-27) +6*a(n-33) -a(n-36) -5*a(n-39) -4*a(n-42) +5*a(n-45) +4*a(n-48) -a(n-51) -2*a(n-54) -a(n-57) +a(n-60).

Example

Some solutions for n=5
..0..0..0..1....0..0..0..2....0..0..0..0....0..0..0..1....0..0..1..1
..0..0..1..1....0..1..1..2....0..0..1..1....0..0..1..2....0..0..1..1
..0..0..1..2....0..1..1..2....0..1..2..2....0..1..2..2....0..0..2..2
..1..1..2..2....0..1..2..2....1..1..2..2....0..1..2..2....0..1..2..2
..2..2..2..2....0..1..2..2....1..1..2..2....1..1..2..2....1..1..2..2

Crossrefs

Column 4 of A201277.

Sequence in context: A032918 A039945 A227302 * A221920 A349663 A188549

Adjacent sequences: A201270 A201271 A201272 * A201274 A201275 A201276

Keyword

nonn,easy

Author

R. H. Hardin, Nov 29 2011

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

Status

approved