A185821 1/5 the number of nX5 0..4 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors

9, 5680, 1266624, 378212944, 100480040192, 28043363244452, 7662203273902712, 2112817100467905536, 580282378007177354752, 159650092398206756238532, 43890600560593534666234904, 12070254095603726713513018032

Offset

1,1

Comments

Column 5 of A185825

Links

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

Example

Some solutions for 4X5 with a(1,1)=0
..0..0..0..2..2....0..0..4..4..0....0..0..3..3..2....0..0..3..3..2
..0..1..0..4..4....0..1..3..4..0....0..1..3..3..2....0..1..0..0..2
..0..1..0..3..3....0..1..3..3..4....0..1..0..2..4....0..1..0..2..4
..0..0..0..1..1....0..0..0..0..4....0..0..0..2..4....0..0..0..2..4

Crossrefs

Sequence in context: A125541 A151581 A145263 * A133248 A125542 A349876

Adjacent sequences: A185818 A185819 A185820 * A185822 A185823 A185824

Keyword

nonn

Author

R. H. Hardin Feb 05 2011

Status

approved