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A186468 Number of (n+1)X6 0..2 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors 1
966, 903, 3190, 4875, 13278, 16083, 40626, 52755, 129102, 182841, 418022, 632281, 1362100, 2157562, 4454506, 7311254, 14630604, 24660486, 48209460, 82892994, 159253412, 277942714, 527083732, 930249586, 1747039708, 3109258106 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A186472

LINKS

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

FORMULA

Empirical: a(n)=2*a(n-1)+a(n-2)-4*a(n-3)+4*a(n-4)-2*a(n-5) for n>14

EXAMPLE

Some solutions for 3X6

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

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

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

CROSSREFS

Sequence in context: A093232 A252259 A225684 * A014363 A260291 A251232

Adjacent sequences:  A186465 A186466 A186467 * A186469 A186470 A186471

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 22 2011

STATUS

approved

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Last modified July 12 09:35 EDT 2020. Contains 335657 sequences. (Running on oeis4.)