A184147 1/4 the number of (n+1)X4 0..3 arrays with every 2X2 subblock having at least two equal elements connected horizontally or vertically

5695, 584143, 58656073, 5910714349, 595270788529, 59956202692285, 6038729388705523, 608216983453837129, 61259186715875932123, 6169982998016034279307, 621436412410878441392839

Offset

1,1

Comments

Column 3 of A184153

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=87*a(n-1)+1672*a(n-2)-27331*a(n-3)-215911*a(n-4)+2529922*a(n-5)-3508448*a(n-6)-9971160*a(n-7)+12988080*a(n-8)+9567936*a(n-9)

Example

Some solutions for 3X4 with a(1,1)=0
..0..0..0..0....0..0..0..3....0..0..0..3....0..0..0..0....0..0..0..1
..3..3..2..0....0..0..3..3....2..3..0..1....1..2..2..2....2..2..3..3
..1..0..2..3....1..0..0..3....2..3..2..2....1..0..0..3....3..3..3..2

Crossrefs

Sequence in context: A204532 A269297 A269344 * A235207 A355317 A252342

Adjacent sequences: A184144 A184145 A184146 * A184148 A184149 A184150

Keyword

nonn

Author

R. H. Hardin Jan 09 2011

Status

approved