A210823 Number of (n+1)X(n+1) 0..3 symmetric matrices containing all values 0..3 with every 2X2 subblock having one, three or four distinct values, and new values 0..3 introduced in lower triangle row major order

0, 18, 1427, 257928, 130771731, 190865023368, 803986090305508, 9774577780098121559, 342988668345739096689603, 34737069299078098520503702785

Offset

1,2

Links

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

Example

Some solutions for n=3
..0..1..3..0....0..1..3..2....0..1..2..3....0..1..0..1....0..1..0..3
..1..2..1..2....1..2..1..3....1..2..0..3....1..2..3..0....1..2..0..1
..3..1..3..1....3..1..3..2....2..0..1..1....0..3..0..1....0..0..3..0
..0..2..1..2....2..3..2..0....3..3..1..1....1..0..1..2....3..1..0..1

Crossrefs

Sequence in context: A275047 A160252 A276015 * A258336 A211310 A160307

Adjacent sequences: A210820 A210821 A210822 * A210824 A210825 A210826

Keyword

nonn

Author

R. H. Hardin Mar 27 2012

Status

approved