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A206340 Number of (n+1)X6 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor 1
1376, 686, 4007, 2034, 12021, 6090, 36015, 18222, 107997, 54618, 323943, 163806, 971799, 491406, 2915385, 1474206, 8746143, 4422606, 26238417, 13267806, 78715239, 39803406, 236145705, 119410206, 708437103, 358230606, 2125311297 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A206343

LINKS

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

FORMULA

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

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A258964 A045131 A056049 * A056087 A122692 A076760

Adjacent sequences:  A206337 A206338 A206339 * A206341 A206342 A206343

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 06 2012

STATUS

approved

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Last modified January 20 19:53 EST 2020. Contains 331096 sequences. (Running on oeis4.)