login
A211109
1/4 the number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having two, three or four distinct values
1
15, 891, 208575, 192515373, 700590250755, 10052185332068649, 568662258529219221297, 126836971252795362522842613, 111541083171262765512515480985165
OFFSET
1,1
LINKS
EXAMPLE
Some solutions for n=3
..2..2..3..1....2..2..1..3....0..0..0..0....0..0..1..2....2..0..3..1
..2..0..0..1....2..0..1..3....0..2..2..0....0..2..1..3....0..2..3..0
..3..0..1..2....1..1..1..0....0..2..1..2....1..1..3..2....3..3..0..2
..1..1..2..1....3..3..0..1....0..0..2..3....2..3..2..3....1..0..2..0
CROSSREFS
Sequence in context: A258796 A232364 A264562 * A249963 A157462 A268166
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2012
STATUS
approved