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A195957 Number of nX3 0..4 arrays with each element equal to the number its horizontal and vertical neighbors unequal to itself 1
2, 6, 10, 16, 21, 44, 82, 144, 273, 531, 1032, 1960, 3805, 7446, 14505, 28254, 55311, 108511, 212645, 417039, 819145, 1609692, 3163058, 6217976, 12229218, 24055201, 47320658, 93104592, 183213156, 360551489, 709578685, 1396577604, 2748853048 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A195962
LINKS
FORMULA
Empirical: a(n) = 2*a(n-2) +5*a(n-3) +5*a(n-4) -4*a(n-5) -15*a(n-6) -14*a(n-7) -a(n-8) +10*a(n-9) +2*a(n-10) -16*a(n-11) -15*a(n-12) +9*a(n-13) +29*a(n-14) +20*a(n-15) -2*a(n-16) -10*a(n-17) -4*a(n-18)
EXAMPLE
Some solutions for n=5
..1..1..1....1..1..1....1..1..1....2..3..2....2..3..2....2..3..2....2..1..1
..2..2..2....2..3..2....3..4..3....3..4..3....3..4..3....1..1..1....1..1..3
..3..4..3....2..3..2....2..2..2....2..2..2....2..2..2....1..1..1....1..1..1
..2..2..2....3..4..3....3..4..3....3..4..3....3..4..3....3..4..3....3..4..1
..1..1..1....1..1..1....1..1..1....2..3..2....1..1..1....1..1..1....2..3..1
CROSSREFS
Sequence in context: A124198 A032426 A220453 * A354425 A294013 A183575
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 25 2011
STATUS
approved

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Last modified April 17 01:50 EDT 2024. Contains 371756 sequences. (Running on oeis4.)