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A205021
Number of (n+1)X3 0..3 arrays with the determinants of 2X2 subblocks nondecreasing rightwards and downwards
1
2338, 27611, 275853, 3684581, 56088455, 888172440, 14267356381, 230651852383, 3739445935138, 60705486742742, 986065323772866, 16021434746669572, 260345712140671916, 4230813125922375591, 68755635262011437219
OFFSET
1,1
COMMENTS
Column 2 of A205027
LINKS
FORMULA
Empirical: a(n) = 24*a(n-1) -102*a(n-2) -656*a(n-3) +4911*a(n-4) -9576*a(n-5) +5400*a(n-6) for n>21
EXAMPLE
Some solutions for n=4
..2..0..2....1..0..0....0..3..0....0..0..1....0..1..0....0..0..2....0..3..3
..3..0..1....3..0..0....2..0..0....0..0..1....0..0..0....1..0..0....1..3..2
..0..0..3....1..0..3....1..0..1....1..0..0....1..0..2....1..0..2....2..3..1
..2..0..1....1..0..2....1..0..0....3..0..1....3..0..1....2..0..0....2..2..0
..0..0..2....1..0..1....2..0..3....1..0..3....2..0..2....1..0..0....1..3..2
CROSSREFS
Sequence in context: A166581 A237387 A212466 * A207296 A043440 A023938
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 21 2012
STATUS
approved