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A233220
Number of 4Xn 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order
1
48, 10313, 3638416, 1340889772, 496475792293, 183912498314536, 68131170547319605, 25239611378677465012, 9350174239701150626293, 3463831582475143352295856, 1283198472110498311312723525
OFFSET
1,1
COMMENTS
Row 4 of A233217
LINKS
FORMULA
Empirical: a(n) = 463*a(n-1) -37470*a(n-2) +1233734*a(n-3) -20184680*a(n-4) +174604620*a(n-5) -799830930*a(n-6) +1856211162*a(n-7) -1978514343*a(n-8) +766517445*a(n-9) for n>12
EXAMPLE
Some solutions for n=2
..0..1....0..1....0..1....0..1....0..1....0..0....0..0....0..1....0..1....0..1
..2..4....2..2....1..1....2..2....1..0....1..0....1..5....2..1....0..2....2..0
..4..2....1..2....2..2....4..3....2..2....0..0....1..2....2..0....0..2....1..3
..4..4....5..1....4..4....1..1....5..4....4..2....5..5....3..3....0..4....0..1
CROSSREFS
Sequence in context: A232160 A260212 A295590 * A377749 A123478 A275570
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 06 2013
STATUS
approved