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A186788 Half the number of (n+2)X3 binary arrays with each 3X3 subblock having a sum in 2..7 1
246, 1910, 14825, 115069, 893145, 6932452, 53808589, 417653681, 3241761282, 25162034228, 195303697871, 1515916163938, 11766299569341, 91328141257666, 708874471232044, 5502170623914248, 42706971125717460, 331484700748035803 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A186796

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=7*a(n-1)+4*a(n-2)+15*a(n-3)-9*a(n-5)

EXAMPLE

Some solutions for 4X3 with a(1,1)=0

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

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

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

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

CROSSREFS

Sequence in context: A067916 A229577 A186796 * A074995 A251524 A251517

Adjacent sequences:  A186785 A186786 A186787 * A186789 A186790 A186791

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 26 2011

STATUS

approved

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Last modified September 24 22:31 EDT 2017. Contains 292441 sequences.