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.

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

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 * A361487 A023095 A044326

Adjacent sequences: A260535 A260536 A260537 * A260539 A260540 A260541

Keyword

nonn

Author

R. H. Hardin, Jul 28 2015

Status

approved