A207230 Number of nX3 0..2 arrays avoiding the patterns z z+1 z or z z-1 z in any row, column, diagonal or antidiagonal

23, 529, 5853, 79353, 1089017, 14540437, 191801477, 2533992385, 33633408281, 446969194245, 5934335699013, 78734145422409, 1044643855277649, 13863317628561493, 183990202045624685, 2441770188415757129

Offset

1,1

Comments

Column 3 of A207235

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -84*a(n-2) +531*a(n-3) +1301*a(n-4) -257*a(n-5) +17030*a(n-6) -106*a(n-7) -212554*a(n-8) -1296056*a(n-9) +155344*a(n-10) +7596656*a(n-11) +2224800*a(n-12) -11493056*a(n-13) -26888992*a(n-14) -43257728*a(n-15) -8055680*a(n-16) -42288128*a(n-17) -40871936*a(n-18) -16979968*a(n-19) -18243584*a(n-20) +92192768*a(n-21) +1687552*a(n-22) +123764736*a(n-23) -22282240*a(n-24) -27852800*a(n-25) for n>28

Example

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

Crossrefs

Sequence in context: A332797 A057193 A014960 * A207223 A207010 A171297

Adjacent sequences: A207227 A207228 A207229 * A207231 A207232 A207233

Keyword

nonn

Author

R. H. Hardin Feb 16 2012

Status

approved