A252946 Number of (n+2)X(2+2) 0..2 arrays with every consecutive three elements in every row, column and nw-se diagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

747, 2988, 12915, 57978, 262494, 1192149, 5419521, 24648309, 112122162, 510068277, 2320483212, 10556851032, 48027819627, 218500501500, 994059717210, 4522438970532, 20574677747547, 93603784061979, 425847190478391

Offset

1,1

Comments

Column 2 of A252952

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -5*a(n-2) -8*a(n-3) +4*a(n-4) -7*a(n-5) +14*a(n-6) +19*a(n-7) -14*a(n-8) -12*a(n-9) -24*a(n-10) -47*a(n-11) +18*a(n-12) +31*a(n-13) +7*a(n-14) +40*a(n-15) -5*a(n-16) +a(n-17) -11*a(n-18) -12*a(n-19) +2*a(n-20) +5*a(n-21) -a(n-22)

Example

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

Crossrefs

Sequence in context: A235513 A252560 A252453 * A242150 A184024 A378538

Adjacent sequences: A252943 A252944 A252945 * A252947 A252948 A252949

Keyword

nonn

Author

R. H. Hardin, Dec 25 2014

Status

approved