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A211108
1/4 the number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having one, three or four distinct values
0
7, 145, 8869, 1551481, 784712137, 1145192936557, 4823916698572867, 58647466694975620939, 2057932010076596938468321, 208422415794469123178956493563
OFFSET
1,1
EXAMPLE
Some solutions for n=3
..2..0..2..1....2..1..1..2....3..1..2..0....2..0..1..2....1..0..3..0
..0..1..3..1....1..0..3..0....1..0..1..1....0..3..2..3....0..3..1..0
..2..3..2..1....1..3..1..3....2..1..3..2....1..2..1..0....3..1..2..2
..1..1..1..0....2..0..3..2....0..1..2..0....2..3..0..3....0..0..2..2
CROSSREFS
Sequence in context: A102059 A064624 A342113 * A251668 A373881 A376227
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2012
STATUS
approved