A196925 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 1,4,3,2,0 for x=0,1,2,3,4

1, 1, 2, 7, 65, 1242, 55546, 5603265, 1280956817, 661075536443, 771059112373171, 2031433178217758354

Offset

1,3

Comments

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

Diagonal of A196929

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Sequence in context: A179043 A116985 A042051 * A246865 A133237 A099660

Adjacent sequences: A196922 A196923 A196924 * A196926 A196927 A196928

Keyword

nonn

Author

R. H. Hardin Oct 07 2011

Status

approved