A230670 Number of n X 3 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).

3, 87, 1173, 17271, 251595, 3669765, 53519163, 780527655, 11383251453, 166013909415, 2421155095347, 35310246222069, 514966385300499, 7510295349852327, 109530520538219973, 1597398553655896551

Offset

1,1

Comments

Column 3 of A230675.

Links

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

Formula

Empirical: a(n) = 14*a(n-1) +9*a(n-2) -9*a(n-3) +30*a(n-4) -19*a(n-5).

Empirical g.f.: 3*x*(1 + 15*x - 24*x^2 + 31*x^3 - 21*x^4) / (1 - 14*x - 9*x^2 + 9*x^3 - 30*x^4 + 19*x^5). - Colin Barker, Feb 09 2018

Example

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

Crossrefs

Sequence in context: A172494 A279131 A368620 * A232069 A172723 A331645

Adjacent sequences: A230667 A230668 A230669 * A230671 A230672 A230673

Keyword

nonn

Author

R. H. Hardin, Oct 27 2013

Status

approved