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A240889
Number of nX4 0..2 arrays with no element equal to a different number of vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order
1
4, 36, 289, 2362, 19065, 154858, 1255585, 10186158, 82615013, 670126562, 5435464261, 44088312610, 357608156789, 2900631278142, 23527575671521, 190836751334954, 1547913820098569, 12555429390762018, 101839521640750945
OFFSET
1,1
COMMENTS
Column 4 of A240893
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) +9*a(n-2) -63*a(n-3) +36*a(n-4) -405*a(n-5) -608*a(n-6) +600*a(n-7) +424*a(n-8) +4600*a(n-9) +10176*a(n-10) +9216*a(n-11) -2560*a(n-12) -29312*a(n-13) -40448*a(n-14) -30720*a(n-15) -16384*a(n-16)
EXAMPLE
Some solutions for n=4
..0..1..2..1....0..1..2..1....0..1..2..0....0..1..2..1....0..1..0..2
..2..0..1..0....1..0..1..2....1..2..1..2....1..0..1..0....1..0..2..1
..0..2..0..2....0..1..0..1....2..0..2..0....0..2..0..2....0..2..1..0
..2..0..1..0....2..0..1..2....0..2..1..2....2..0..1..0....2..1..0..1
CROSSREFS
Sequence in context: A180170 A277174 A059416 * A108019 A241104 A373339
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 14 2014
STATUS
approved