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A210819
Number of (n+1) X (n+1) 0..3 symmetric matrices containing all values 0..3 with every 2 X 2 subblock having one, two or three distinct values, and new values 0..3 introduced in lower triangle row major order.
1
0, 49, 23161, 22911278, 69542484194, 729154389280269, 27471650645869518237, 3762964490348482852461426, 1879310211105558770807436764190, 3424003001550934968214802269585406825
OFFSET
1,2
LINKS
EXAMPLE
Some solutions for n=3
..0..1..1..1....0..0..1..1....0..1..2..3....0..1..0..3....0..1..1..2
..1..1..1..3....0..1..1..1....1..2..1..3....1..2..2..2....1..2..0..2
..1..1..2..3....1..1..1..2....2..1..0..1....0..2..2..0....1..0..3..0
..1..3..3..2....1..1..2..3....3..3..1..2....3..2..0..2....2..2..0..1
CROSSREFS
Sequence in context: A013741 A178190 A319941 * A173171 A100418 A369698
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 27 2012
STATUS
approved