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A233225
Number of nX3 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally, diagonally, antidiagonally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order
1
6, 174, 8231, 420948, 21895530, 1142726121, 59679029456, 3117164734533, 162820623245643, 8504746957840386, 444236096357832461, 23204188477204907670, 1212045554583039193836, 63309882191615788539747
OFFSET
1,1
COMMENTS
Column 3 of A233230
LINKS
FORMULA
Empirical: a(n) = 66*a(n-1) -748*a(n-2) +1422*a(n-3) +5006*a(n-4) -16598*a(n-5) +10288*a(n-6) +8658*a(n-7) -10189*a(n-8) +2228*a(n-9) -132*a(n-10)
EXAMPLE
Some solutions for n=3
..0..0..1....0..1..5....0..0..1....0..1..2....0..1..2....0..1..2....0..1..1
..0..1..0....1..1..2....2..1..3....2..0..2....2..1..0....0..1..1....0..0..2
..1..2..2....3..1..2....0..1..5....2..2..0....2..0..1....0..3..3....1..2..2
CROSSREFS
Sequence in context: A166762 A323279 A214801 * A055165 A318538 A071095
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 06 2013
STATUS
approved