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A232061 Number of nX4 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or vertically, with no adjacent values equal 1
6, 30, 130, 534, 2230, 9310, 38870, 162278, 677510, 2828606, 11809446, 49304494, 205846518, 859410282, 3588042398, 14980095674, 62541977366, 261113080850, 1090148470882, 4551375536978, 19002016543538, 79333517919430 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A232065

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 4*a(n-1) +a(n-2) -4*a(n-4) -3*a(n-5) +a(n-7) +3*a(n-8) -a(n-11)

EXAMPLE

Some solutions for n=7

..1..0..1..2....0..1..0..1....1..2..1..0....2..0..1..2....2..1..2..1

..2..1..0..1....1..2..1..2....0..1..0..2....0..2..0..1....1..2..1..0

..1..2..1..0....2..1..2..1....1..0..2..1....1..0..1..0....2..1..2..1

..2..0..2..1....1..0..1..2....2..1..0..2....2..1..2..1....1..2..1..0

..0..1..0..2....2..1..0..1....1..2..1..0....0..2..1..2....2..1..2..1

..1..2..1..0....1..2..1..2....2..1..2..1....1..0..2..1....1..2..1..0

..2..1..0..2....0..1..2..1....1..0..1..2....2..1..0..2....0..1..2..1

CROSSREFS

Sequence in context: A261389 A073389 A320744 * A247386 A317755 A036068

Adjacent sequences:  A232058 A232059 A232060 * A232062 A232063 A232064

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 17 2013

STATUS

approved

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Last modified April 6 16:14 EDT 2020. Contains 333276 sequences. (Running on oeis4.)