A184370 1/3 the number of (n+1)X4 0..2 arrays with every 2X2 subblock having at least two equal elements connected horizontally or vertically

1107, 49235, 2167173, 95528423, 4210059673, 185547841629, 8177524177277, 360402692568245, 15883791500540967, 700035935394350709, 30852225032929689819, 1359729896274471875219, 59926484677950059719491

Offset

1,1

Comments

Column 3 of A184376

Links

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

Formula

Empirical: a(n)=38*a(n-1)+302*a(n-2)-1368*a(n-3)-6770*a(n-4)+12666*a(n-5)-575*a(n-6)-5790*a(n-7)+828*a(n-8)+648*a(n-9)

Example

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

Crossrefs

Sequence in context: A157376 A185501 A322535 * A172638 A278633 A278413

Adjacent sequences: A184367 A184368 A184369 * A184371 A184372 A184373

Keyword

nonn

Author

R. H. Hardin Jan 12 2011

Status

approved