A210830 Number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having one or three distinct values, and new values 0..3 introduced in lower triangle row major order

2, 21, 836, 82199, 19344902, 10875989293, 14610163237856, 46893874745455135, 359629516402454786058, 6589801210450509598836041

Offset

1,1

Links

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

Example

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

Crossrefs

Sequence in context: A376689 A113083 A174964 * A139164 A019994 A015193

Adjacent sequences: A210827 A210828 A210829 * A210831 A210832 A210833

Keyword

nonn

Author

R. H. Hardin Mar 27 2012

Status

approved