A260202 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001.

106, 207, 685, 1857, 5291, 15715, 45181, 129853, 377479, 1091843, 3153331, 9128061, 26409885, 76369661, 220928809, 639119931, 1848648749, 5347522963, 15468867253, 44745801211, 129434159209, 374410717115, 1083042439267, 3132872536335

Offset

1,1

Links

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

Formula

Empirical: a(n) = a(n-1) + 2*a(n-2) + 9*a(n-3) + 6*a(n-4) - 3*a(n-5) - 10*a(n-6) - 17*a(n-7) - 7*a(n-8) + 12*a(n-9) + 12*a(n-10) - 6*a(n-11) for n>12.

Empirical g.f.: x*(106 + 101*x + 266*x^2 - 196*x^3 - 435*x^4 - 379*x^5 - 258*x^6 + 408*x^7 + 765*x^8 + 4*x^9 - 570*x^10 + 186*x^11) / (1 - x - 2*x^2 - 9*x^3 - 6*x^4 + 3*x^5 + 10*x^6 + 17*x^7 + 7*x^8 - 12*x^9 - 12*x^10 + 6*x^11). - Colin Barker, Dec 28 2018

Example

Some solutions for n=4:
..1..0..0..0..1....0..0..0..0..0....0..0..1..0..0....0..0..0..0..1
..0..0..0..0..0....0..1..0..0..1....0..0..0..0..0....0..0..0..1..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....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....0..0..0..0..0
..0..0..0..0..0....0..0..0..0..1....0..1..0..0..1....0..0..0..0..1

Crossrefs

Column 3 of A260207.

Sequence in context: A160725 A044338 A044719 * A255818 A090775 A213458

Adjacent sequences: A260199 A260200 A260201 * A260203 A260204 A260205

Keyword

nonn

Author

R. H. Hardin, Jul 19 2015

Status

approved