A186596 Number of (n+3)X9 0..3 arrays with every 4X4 subblock commuting with each horizontal and vertical neighbor 4X4 subblock

53301263, 884466, 1824789, 5654805, 12478581, 16898709, 17002221, 17171973, 17632173, 19933269, 23358789, 28260813, 48277797, 77435613, 110277237, 176424504, 289297251, 436495782, 605022297, 888171813, 1371548721, 2045376429

Offset

1,1

Comments

Column 6 of A186599

Links

R. H. Hardin, Table of n, a(n) for n = 1..41

Formula

Empirical: a(n)=2*a(n-1)-a(n-2)+3*a(n-4)-6*a(n-5)+3*a(n-6)+3*a(n-8)-3*a(n-9) for n>16

Example

Some solutions for 5X9
..0..0..0..0..0..0..0..2..0....0..0..0..0..0..0..1..1..1
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..1..1
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..1
..0..0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0..0
..2..2..0..0..0..0..0..0..1....0..0..2..0..0..0..0..0..0

Crossrefs

Sequence in context: A105381 A004672 A029824 * A205180 A216007 A186794

Adjacent sequences: A186593 A186594 A186595 * A186597 A186598 A186599

Keyword

nonn

Author

R. H. Hardin Feb 24 2011

Status

approved