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A237489
Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the upper median minus the lower median minus the minimum of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
1
256, 1728, 11960, 84000, 589944, 4135648, 28986208, 203229696, 1425235712, 9994034688, 70063673600, 491213816320, 3444698036992, 24155061404672, 169341502948352, 1187245857484800, 8325697972232192, 58381830568157184
OFFSET
1,1
COMMENTS
Column 1 of A237494
LINKS
FORMULA
Empirical: a(n) = 2568*a(n-4) -371328*a(n-8) +15212544*a(n-12) -125530112*a(n-16) +93167616*a(n-20) -143392768*a(n-24) for n>27
EXAMPLE
Some solutions for n=4
..0..3....1..0....1..3....3..2....2..2....3..0....2..2....1..0....1..2....0..3
..2..3....3..0....2..2....3..3....2..0....3..0....2..1....0..2....3..1....0..1
..3..1....3..3....3..0....2..2....2..3....2..0....1..2....0..0....2..0....3..1
..3..3....0..2....2..1....2..1....0..1....1..3....2..0....1..0....3..0....2..2
..2..3....1..2....1..3....0..1....2..2....0..1....1..1....2..1....1..2....0..3
CROSSREFS
Sequence in context: A237936 A237931 A237494 * A238054 A238049 A237785
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 08 2014
STATUS
approved