A302422 Number of nX3 0..1 arrays with every element equal to 0, 1, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

3, 9, 11, 21, 51, 93, 207, 517, 1007, 2333, 5847, 11781, 27055, 66861, 137895, 314197, 766367, 1610429, 3649239, 8799333, 18772687, 42381645, 101181063, 218513269, 492148223, 1164905693, 2540589879, 5713965957, 13425837103, 29512490349

Offset

1,1

Comments

Column 3 of A302427.

Links

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

Formula

Empirical: a(n) = a(n-1) +10*a(n-3) -8*a(n-4) for n>9

Example

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

Crossrefs

Cf. A302427.

Sequence in context: A370918 A331029 A105949 * A032665 A331832 A032915

Adjacent sequences: A302419 A302420 A302421 * A302423 A302424 A302425

Keyword

nonn

Author

R. H. Hardin, Apr 07 2018

Status

approved