A192767 Number of n X n symmetric 0..4 arrays with each element equal to at least one horizontal or vertical neighbor, containing at least one 4 and with new values 0..4 introduced in lower triangular row major order

0, 0, 0, 0, 2432, 5693147, 22718529036, 246577454328217, 8154425735827153538, 877838603725481966872516

Offset

1,5

Links

Table of n, a(n) for n=1..10.

Example

Some solutions for 5X5
..0..0..2..2..2....0..0..1..2..4....0..0..0..2..4....0..0..0..2..2
..0..1..1..2..0....0..1..1..2..4....0..0..1..2..4....0..1..1..3..2
..2..1..3..3..0....1..1..1..3..3....0..1..1..3..4....0..1..1..3..4
..2..2..3..3..4....2..2..3..0..0....2..2..3..3..3....2..3..3..3..4
..2..0..0..4..4....4..4..3..0..0....4..4..4..3..3....2..2..4..4..4

Crossrefs

Sequence in context: A202201 A147984 A229871 * A341286 A250710 A278196

Adjacent sequences: A192764 A192765 A192766 * A192768 A192769 A192770

Keyword

nonn

Author

R. H. Hardin Jul 09 2011

Status

approved