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A209521
Number of nX2 0..7 arrays with every 2X2 subblock containing exactly one value repeat, and new values 0..7 introduced in row major order
1
2, 6, 57, 700, 10677, 193676, 4054358, 95534880, 2472405340, 68613576496, 1999809519672, 60231323048000, 1853103730499696, 57790053276242496, 1817609007303894496, 57472115932658904064, 1823283879810883824576
OFFSET
1,1
COMMENTS
Column 2 of A209527
LINKS
FORMULA
Empirical: a(n) = 68*a(n-1) -1410*a(n-2) +5696*a(n-3) +105944*a(n-4) -757536*a(n-5) -1207008*a(n-6) +7568640*a(n-7) +13260672*a(n-8) +4354560*a(n-9) for n>10
EXAMPLE
Some solutions for n=5
..0..0....0..0....0..0....0..0....0..0....0..0....0..1....0..0....0..0....0..0
..1..2....1..2....1..2....1..2....1..2....1..2....0..2....1..2....1..2....1..2
..0..1....0..1....0..2....0..0....0..0....1..3....0..1....0..0....0..0....1..3
..2..0....0..2....3..0....3..4....1..2....0..3....3..3....1..2....2..3....0..0
..0..1....1..0....0..1....0..3....2..0....3..4....2..0....0..0....0..0....1..2
CROSSREFS
Sequence in context: A209497 A209738 A209459 * A357026 A366366 A357092
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 10 2012
STATUS
approved