A223053 Number of 2Xn 0..3 arrays with exactly floor(2Xn/2) elements equal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..3 order

0, 4, 44, 508, 6918, 93770, 1302140, 18203855, 255963118, 3621617164, 51457102852, 733976768254, 10502362067962, 150690052903934, 2167251949580988, 31234643654675360, 450981145373780394, 6522104011884246116

Offset

1,2

Comments

Row 2 of A223052

Links

R. H. Hardin, Table of n, a(n) for n = 1..61

Example

Some solutions for n=3
..0..1..0....0..1..2....0..1..0....0..0..1....0..1..0....0..0..1....0..1..0
..1..1..2....2..0..0....1..1..0....1..0..1....2..0..3....2..0..1....2..2..2

Crossrefs

Sequence in context: A087813 A342346 A082779 * A222288 A053315 A005721

Adjacent sequences: A223050 A223051 A223052 * A223054 A223055 A223056

Keyword

nonn

Author

R. H. Hardin Mar 13 2013

Status

approved