A184666 Number of (n+1)X3 0..3 arrays with no 2X2 subblock summing to less than 6

1740, 67330, 2405797, 88458672, 3225439429, 117938741095, 4308670152724, 157454260497016, 5753418267657560, 210237556594325891, 7682287249431007868, 280719194120503850605, 10257776899125672523995, 374830158857789457998588

Offset

1,1

Comments

Column 2 of A184673

Links

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

Formula

Empirical: a(n)=33*a(n-1)+254*a(n-2)-4528*a(n-3)-4583*a(n-4)+136276*a(n-5)-51684*a(n-6)-1465238*a(n-7)+1162805*a(n-8)+7140128*a(n-9)-6753172*a(n-10)-16991713*a(n-11)+16867228*a(n-12)+20582754*a(n-13)-20497813*a(n-14)-13213038*a(n-15)+12962168*a(n-16)+4464952*a(n-17)-4283552*a(n-18)-731808*a(n-19)+687168*a(n-20)+44928*a(n-21)-41472*a(n-22)

Example

Some solutions for 5X3
..0..2..2....0..2..2....0..2..2....0..2..0....0..2..0....0..2..2....0..2..2
..2..2..2....2..2..2....2..2..2....2..2..3....2..2..2....2..2..0....2..2..3
..2..1..1....2..2..1....0..3..0....2..0..3....2..2..3....2..2..3....2..0..3
..0..3..2....1..3..3....0..3..3....3..1..3....2..3..1....3..3..1....1..3..0
..3..0..3....3..1..1....0..3..0....0..2..0....3..3..0....2..1..2....3..2..1

Crossrefs

Sequence in context: A259302 A251802 A251324 * A022061 A107525 A185942

Adjacent sequences: A184663 A184664 A184665 * A184667 A184668 A184669

Keyword

nonn

Author

R. H. Hardin Jan 19 2011

Status

approved