A252858 Number of (n+2)X(5+2) 0..2 arrays with every consecutive three elements in every row, column, diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

4383, 2502, 3582, 7002, 14229, 28728, 58644, 119727, 245016, 501462, 1027503, 2103156, 4308210, 8823537, 18075114, 37017972, 75824523, 155304774, 318115530, 651566331, 1334582154, 2733553872, 5599070757, 11468280366, 23490006084

Offset

1,1

Comments

Column 5 of A252861

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-2) +4*a(n-4) -4*a(n-5) -7*a(n-6) -a(n-7) +3*a(n-8) +9*a(n-9) -3*a(n-10) -3*a(n-11) -2*a(n-12) +2*a(n-14) +a(n-15) -a(n-16) for n>18

Example

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

Crossrefs

Sequence in context: A203874 A205317 A252645 * A027506 A343828 A345180

Adjacent sequences: A252855 A252856 A252857 * A252859 A252860 A252861

Keyword

nonn

Author

R. H. Hardin, Dec 23 2014

Status

approved