A184780 Number of (n+2)X3 0..2 arrays with each 3X3 subblock nonsingular

12792, 260268, 5299212, 107810856, 2193592920, 44633574216, 908160565032, 18478374229416, 375980327644488, 7650088026679752, 155656671056370024, 3167153029248451944, 64442199825855185928, 1311208229754332950152

Offset

1,1

Comments

Column 1 of A184784

Links

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

Formula

Empirical: a(n)=4*a(n-1)+123*a(n-2)+2670*a(n-3)+22675*a(n-4)+159996*a(n-5)+683337*a(n-6)+2159142*a(n-7)+2203254*a(n-8)-10791668*a(n-9)-60946844*a(n-10)-139654560*a(n-11)+113218448*a(n-12)+853157504*a(n-13)+1692141376*a(n-14)-914983808*a(n-15)-12472539648*a(n-16)+666559488*a(n-17)+33631735808*a(n-18)-11806212096*a(n-19)-31261982720*a(n-20)+19818086400*a(n-21)

Example

Some solutions for 4X3
..0..2..2....1..0..0....0..1..0....0..0..1....0..0..2....0..2..0....1..0..0
..1..0..0....1..0..1....2..0..2....2..0..0....1..2..2....1..0..2....0..0..2
..2..1..0....1..1..2....2..0..0....0..2..1....1..0..2....0..1..2....0..2..1
..1..1..2....0..0..2....2..1..0....0..1..2....0..1..1....2..1..2....2..2..1

Crossrefs

Sequence in context: A203273 A217184 A184784 * A206796 A206966 A209091

Adjacent sequences: A184777 A184778 A184779 * A184781 A184782 A184783

Keyword

nonn

Author

R. H. Hardin Jan 21 2011

Status

approved