A195970 - OEIS

A195970

Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,1,3,4 for x=0,1,2,3,4

1, 9, 24, 67, 244, 1280, 5637, 32909, 212185, 1609756, 13476199, 134461394

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

OFFSET

1,2

COMMENTS

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 3's, every 4 is next to 4 4's

Diagonal of A195978

LINKS

EXAMPLE

Some solutions for n=4

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

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

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

..1..0..0..1....1..1..0..1....0..1..1..0....1..0..1..1....1..0..0..0

CROSSREFS

KEYWORD

nonn

AUTHOR

STATUS

approved