A204310 Number of (n+2)X3 0..2 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..2 introduced in row major order

2064, 39669, 781827, 15015804, 289666498, 5600593083, 108143812341, 2088355492268, 40334436464660, 778971744247541, 15044080885441801, 290545241514740108, 5611265991208953802, 108369650847239205573

Offset

1,1

Comments

Column 1 of A204314

Links

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

Formula

Empirical: a(n) = 19*a(n-1) -21*a(n-2) +804*a(n-3) -5651*a(n-4) +5422*a(n-5) -29948*a(n-6) +48563*a(n-7) +377751*a(n-8) +182225*a(n-9) +376001*a(n-10) -1944354*a(n-11) -4661689*a(n-12) -2878602*a(n-13) -2840090*a(n-14) +4524915*a(n-15) +5688082*a(n-16) -1392732*a(n-17) +2105766*a(n-18) +2721236*a(n-19) +379776*a(n-20) -3810696*a(n-21) -1488176*a(n-22) +1146536*a(n-23) +1106592*a(n-24) +982704*a(n-25) -393984*a(n-26) -286848*a(n-27) +86400*a(n-28)

Example

Some solutions for n=3
..0..1..1....0..0..0....0..1..1....0..0..1....0..0..0....0..1..0....0..1..0
..1..0..2....1..2..1....1..0..1....2..2..2....1..0..2....2..2..0....2..0..1
..1..2..0....2..2..0....2..2..1....1..2..1....1..2..1....1..0..0....2..0..0
..2..0..2....0..0..0....0..1..1....0..2..2....2..2..1....2..0..0....0..0..2
..1..1..1....2..0..0....0..0..0....0..0..0....2..0..1....1..0..2....1..1..1

Crossrefs

Sequence in context: A234110 A200203 A204314 * A168432 A256744 A015993

Adjacent sequences: A204307 A204308 A204309 * A204311 A204312 A204313

Keyword

nonn

Author

R. H. Hardin Jan 14 2012

Status

approved