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A260538 Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010001. 1
75, 131, 310, 566, 976, 2229, 4296, 7576, 16060, 32285, 58636, 118158, 240124, 449449, 881000, 1782816, 3414548, 6616199, 13258972, 25773006, 49827510, 98896019, 193756928, 375388238, 739657558, 1453670523, 2825958650, 5543030018 (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-2) + 5*a(n-3) + 4*a(n-4) - 3*a(n-5) - 2*a(n-6) - 10*a(n-8) - 6*a(n-9) + a(n-10) - a(n-11) + a(n-12) + a(n-13) for n>14.

Empirical g.f.: x*(75 + 131*x + 235*x^2 + 60*x^3 - 289*x^4 - 186*x^5 - 207*x^6 - 605*x^7 - 217*x^8 + 133*x^9 - 38*x^10 + 79*x^11 + 45*x^12 - 13*x^13) / (1 - x^2 - 5*x^3 - 4*x^4 + 3*x^5 + 2*x^6 + 10*x^8 + 6*x^9 - x^10 + x^11 - x^12 - x^13). - Colin Barker, Dec 29 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 2 of A260544.

Sequence in context: A224477 A045196 A118225 * A023095 A044326 A044707

Adjacent sequences:  A260535 A260536 A260537 * A260539 A260540 A260541

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 28 2015

STATUS

approved

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Last modified June 26 04:58 EDT 2022. Contains 354877 sequences. (Running on oeis4.)