A207545 Number of nX3 0..2 arrays avoiding the pattern z-2 z-1 z in any row, column, nw-to-se diagonal or ne-to-sw antidiagonal

26, 676, 14974, 327899, 7104784, 153718531, 3323115736, 71828785449, 1552463878141, 33553506212607, 725189754458127, 15673455950921338, 338748698841773309, 7321337736630455158, 158235245543724632042

Offset

1,1

Comments

Column 3 of A207550

Links

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

Formula

Empirical: a(n) = 25*a(n-1) -14*a(n-2) -1439*a(n-3) +2416*a(n-4) +24494*a(n-5) -42148*a(n-6) -155315*a(n-7) +298717*a(n-8) +465648*a(n-9) -796742*a(n-10) -772730*a(n-11) -248746*a(n-12) +448619*a(n-13) +4500187*a(n-14) +1535833*a(n-15) -6305900*a(n-16) -2969844*a(n-17) +2515810*a(n-18) +1396963*a(n-19) +20165*a(n-20) +11517*a(n-21) -177480*a(n-22) -113665*a(n-23) +8548*a(n-24) +5517*a(n-25) +252*a(n-26)

Example

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

Crossrefs

Sequence in context: A207715 A208076 A207551 * A207312 A218063 A206695

Adjacent sequences: A207542 A207543 A207544 * A207546 A207547 A207548

Keyword

nonn

Author

R. H. Hardin Feb 18 2012

Status

approved