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A206342 Number of (n+1)X8 0..3 arrays with every 2X2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor 1
4111, 2042, 12005, 6078, 36015, 18258, 108141, 54762, 324087, 163950, 971925, 491514, 2915439, 1474206, 8746143, 4422606, 26238417, 13267806, 78715239, 39803406, 236145705, 119410206, 708437103, 358230606, 2125311297, 1074691806 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 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>16

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A077190 A204530 A204526 * A031828 A205581 A061325

Adjacent sequences:  A206339 A206340 A206341 * A206343 A206344 A206345

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 06 2012

STATUS

approved

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Last modified March 5 11:57 EST 2021. Contains 341823 sequences. (Running on oeis4.)