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A233085
Number of 4Xn 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 in row major order
1
36, 1094, 41675, 1588262, 60632429, 2315298290, 88417171553, 3376534087742, 128945571641429, 4924269835697930, 188051703434648393, 7181459293743807062, 274250946368131595069, 10473300553139406347810, 399962246005236076609073
OFFSET
1,1
COMMENTS
Row 4 of A233082
LINKS
FORMULA
Empirical: a(n) = 49*a(n-1) -450*a(n-2) +1466*a(n-3) -1853*a(n-4) +789*a(n-5) for n>8
EXAMPLE
Some solutions for n=3
..0..1..0....0..0..0....0..1..1....0..0..0....0..1..0....0..1..1....0..1..0
..0..0..2....0..0..1....1..0..1....0..1..0....3..2..3....1..1..1....3..1..3
..0..2..2....2..0..0....1..3..3....0..2..0....2..2..2....1..0..1....3..1..0
..3..3..2....0..1..0....3..1..3....0..1..1....2..0..2....1..0..0....3..2..0
CROSSREFS
Sequence in context: A225830 A000809 A151584 * A215858 A103278 A004294
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 03 2013
STATUS
approved