The On-Line Encyclopedia of Integer Sequences (OEIS)

A206628 revision #4

A206628

Number of (n+1)X2 0..2 arrays with every 2X3 or 3X2 subblock having no more than four equal edges, and new values 0..2 introduced in row major order

14, 121, 1085, 9729, 87238, 782246, 7014246, 62895364, 563970356, 5057011236, 45345224920, 406601711384, 3645917557848, 32692225503376, 293144754758096, 2628571347438864, 23569882170595936, 211346496672826976

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OFFSET

1,1

COMMENTS

Column 1 of A206635

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) +8*a(n-2) +6*a(n-3) for n>4

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A249980 A206635 A163942 * A370966 A235710 A239544

Adjacent sequences: A206625 A206626 A206627 * A206629 A206630 A206631

KEYWORD

nonn

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Feb 10 2012

STATUS

approved