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A260133 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111. 1
138, 342, 1162, 2966, 7698, 22522, 61914, 165954, 462030, 1279574, 3493270, 9617162, 26547878, 72931662, 200533394, 552344746, 1519650534, 4179817642, 11503670758, 31655891034, 87092868954, 239649098010, 659447987986 (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.: 2*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 28 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Column 3 of A260138.

Sequence in context: A202441 A187206 A168531 * A317579 A281592 A213963

Adjacent sequences:  A260130 A260131 A260132 * A260134 A260135 A260136

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 17 2015

STATUS

approved

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Last modified November 30 05:12 EST 2021. Contains 349419 sequences. (Running on oeis4.)