A210820 Number of (n+1)X(n+1) 0..3 symmetric matrices containing all values 0..3 with every 2X2 subblock having two or four distinct values, and new values 0..3 introduced in lower triangle row major order

0, 5, 350, 27048, 3100695, 592034865, 197411860692, 117689225496746, 126916285441085904, 249072860973467032724

Offset

1,2

Links

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

Example

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

Crossrefs

Sequence in context: A300388 A269556 A227448 * A193806 A158105 A203527

Adjacent sequences: A210817 A210818 A210819 * A210821 A210822 A210823

Keyword

nonn

Author

R. H. Hardin Mar 27 2012

Status

approved