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A238049
Number of (n+1)X(1+1) 0..3 arrays with the maximum plus the minimum minus the upper median minus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
1
256, 1760, 12352, 87488, 618752, 4375552, 30949952, 218919168, 1548259072, 10950274048, 77458464768, 547885305856, 3874795835392, 27405049921536, 193853940023296, 1371182905425920, 9697383186169856, 68586135474405376
OFFSET
1,1
COMMENTS
Column 1 of A238054
LINKS
FORMULA
Empirical: a(n) = 2528*a(n-4) -63488*a(n-8) +315392*a(n-12) +147456*a(n-16) +4194304*a(n-20) for n>21
EXAMPLE
Some solutions for n=4
..1..0....3..0....3..0....2..2....0..2....3..3....2..3....0..2....3..0....1..0
..3..3....2..1....0..1....0..0....0..0....1..1....0..0....2..3....1..3....2..2
..0..2....0..0....3..1....2..1....2..1....0..3....3..1....0..1....1..3....3..3
..3..2....1..1....0..0....0..3....1..0....1..2....1..2....2..0....0..3....1..2
..3..2....1..2....1..2....1..1....3..3....0..2....1..0....3..1....3..2....3..0
CROSSREFS
Sequence in context: A237494 A237489 A238054 * A237785 A237780 A237904
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 17 2014
STATUS
approved