A204277 Number of (n+2)X3 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..2 introduced in row major order

108, 274, 783, 1758, 5263, 14141, 29731, 93809, 248919, 573623, 1749927, 4584571, 10749287, 31949583, 84592247, 205786143, 596167847, 1572769159, 3909703655, 11160005367, 29583601447, 74984069415, 210919726503, 560126562599

Offset

1,1

Comments

Column 1 of A204284

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -3*a(n-2) +10*a(n-3) -44*a(n-4) +60*a(n-5) -30*a(n-6) -172*a(n-7) -152*a(n-8) +1224*a(n-9) -448*a(n-10) -656*a(n-11) +880*a(n-12) -2592*a(n-13) +2688*a(n-14) -768*a(n-15) for n>16

Example

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

Crossrefs

Sequence in context: A255084 A252337 A204284 * A138669 A304377 A202616

Adjacent sequences: A204274 A204275 A204276 * A204278 A204279 A204280

Keyword

nonn

Author

R. H. Hardin Jan 13 2012

Status

approved