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A207875 Number of nX4 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 0 and 1 1 1 vertically 1
9, 81, 164, 400, 824, 1940, 4200, 9276, 21004, 46026, 102674, 228630, 506868, 1128070, 2505156, 5569740, 12380188, 27502690, 61145106, 135886522, 301975112, 671190932, 1491685306, 3315241202, 7368059728, 16375432824, 36394465410 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A207879

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-2) +7*a(n-3) +4*a(n-4) -3*a(n-5) -17*a(n-6) -5*a(n-7) +7*a(n-8) +2*a(n-9) -13*a(n-10) -a(n-11) -2*a(n-12) for n>14

EXAMPLE

Some solutions for n=4

..0..1..1..1....0..1..0..0....1..1..0..0....1..0..0..1....0..1..1..0

..1..0..0..1....1..1..0..0....0..0..1..0....0..1..1..1....1..0..0..1

..1..1..1..0....1..0..0..1....0..1..1..0....0..1..1..0....1..1..1..1

..0..1..1..0....0..0..1..1....1..1..0..0....1..0..0..1....0..1..1..0

CROSSREFS

Sequence in context: A343134 A343104 A043180 * A207678 A207684 A207510

Adjacent sequences:  A207872 A207873 A207874 * A207876 A207877 A207878

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 21 2012

STATUS

approved

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Last modified June 24 11:45 EDT 2021. Contains 345416 sequences. (Running on oeis4.)