A192999 Number of n X n symmetric 0..5 arrays with each element equal to at least two horizontal or vertical neighbors and with new values 0..5 introduced in lower triangular row major order

0, 1, 1, 6, 35, 697, 19477, 1547414, 202362287, 65040382838, 35339335932669

Offset

1,4

Links

Table of n, a(n) for n=1..11.

Example

Some solutions for 8X8 containing a 5
..0..0..0..0..0..0..0..0....0..0..1..1..0..0..2..2....0..0..0..1..1..3..3..3
..0..0..1..1..0..0..0..0....0..0..1..1..0..0..2..2....0..0..0..1..1..3..3..3
..0..1..1..1..2..2..4..4....1..1..1..2..2..2..4..4....0..0..1..1..2..2..2..2
..0..1..1..2..2..2..4..4....1..1..2..2..2..2..4..4....1..1..1..1..2..2..2..2
..0..0..2..2..3..3..0..0....0..0..2..2..3..3..5..5....1..1..2..2..0..0..4..4
..0..0..2..2..3..3..0..0....0..0..2..2..3..3..5..5....3..3..2..2..0..0..4..4
..0..0..4..4..0..0..5..5....2..2..4..4..5..5..1..1....3..3..2..2..4..4..5..5
..0..0..4..4..0..0..5..5....2..2..4..4..5..5..1..1....3..3..2..2..4..4..5..5

Crossrefs

Sequence in context: A152128 A115457 A192998 * A193000 A193001 A128298

Adjacent sequences: A192996 A192997 A192998 * A193000 A193001 A193002

Keyword

nonn

Author

R. H. Hardin Jul 14 2011

Status

approved