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A259637 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 or 00000001. 1
69, 171, 581, 1483, 3849, 11261, 30957, 82977, 231015, 639787, 1746635, 4808581, 13273939, 36465831, 100266697, 276172373, 759825267, 2089908821, 5751835379, 15827945517, 43546434477, 119824549005, 329723993993, 907239344187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + a(n-2) + 10*a(n-3) + 4*a(n-4) - 2*a(n-5) - 12*a(n-6) - 5*a(n-7) - 4*a(n-8) + 4*a(n-9) for n>10.

Empirical g.f.: x*(69 + 102*x + 341*x^2 + 41*x^3 - 201*x^4 - 427*x^5 - 137*x^6 - 104*x^7 + 144*x^8 - 12*x^9) / (1 - x - x^2 - 10*x^3 - 4*x^4 + 2*x^5 + 12*x^6 + 5*x^7 + 4*x^8 - 4*x^9). - Colin Barker, Dec 26 2018

EXAMPLE

Some solutions for n=4:

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

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

..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0

..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0

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

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

CROSSREFS

Column 3 of A259642.

Sequence in context: A044401 A044782 A020296 * A211688 A153672 A283053

Adjacent sequences:  A259634 A259635 A259636 * A259638 A259639 A259640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 02 2015

STATUS

approved

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Last modified April 24 04:00 EDT 2019. Contains 322406 sequences. (Running on oeis4.)