A222750 - OEIS

A222750

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

0, 20, 2438, 126947, 6363724, 390671426, 20825891902, 1302002871105, 68980846569683, 4414953646397182, 234735040362399277, 15230133968254421161, 811171016916133624250, 53158538404174454164168, 2835711932391664974150091

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Row 3 of A222747

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..22

EXAMPLE

Some solutions for n=3

..0..1..2....0..1..1....0..0..1....0..1..0....0..1..1....0..1..2....0..1..1

..1..2..0....2..3..3....1..2..0....2..1..2....2..2..1....3..2..0....0..1..2

..1..3..1....0..2..3....1..2..2....1..2..3....1..2..0....3..1..1....1..3..2