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A186478 Number of (n+1)X6 0..3 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors 1
4895, 3442, 20224, 25633, 107353, 108025, 433513, 479785, 1793817, 2226665, 7478693, 10225073, 31371137, 46298817, 132181633, 207648469, 559418905, 924724441, 2376589225, 4095459817, 10129319461, 18060113137, 43291468321 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A186482

LINKS

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

FORMULA

Empirical: a(n)=2*a(n-1)+2*a(n-2)-6*a(n-3)+6*a(n-4)-3*a(n-5) for n>16

EXAMPLE

Some solutions for 3X6

..1..0..0..0..2..1....0..1..0..1..0..1....0..0..0..0..3..0....2..0..1..0..0..0

..1..0..0..0..0..2....3..0..1..0..1..1....0..0..0..0..0..3....0..2..0..1..0..0

..0..1..0..0..0..0....0..3..0..1..1..2....0..0..0..0..0..0....3..0..2..0..1..1

CROSSREFS

Sequence in context: A086127 A126704 A251325 * A220059 A321146 A107545

Adjacent sequences:  A186475 A186476 A186477 * A186479 A186480 A186481

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 22 2011

STATUS

approved

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Last modified November 22 16:31 EST 2019. Contains 329396 sequences. (Running on oeis4.)