A185884 1/729 the number of (n+2)X4 0..2 arrays with no 3X3 subblock trace equal to any horizontal or vertical neighbor 3X3 subblock trace

588, 28086, 1367896, 66642628, 3246601822, 158165462152, 7705358302364, 375382835991994, 18287564821580820, 890917264229752280, 43402911480566404166, 2114464283378121452876, 103010582623598272525692

Offset

1,1

Comments

Column 2 of A185891

Links

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

Formula

Empirical: a(n)=20*a(n-1)+1233*a(n-2)+8989*a(n-3)-39476*a(n-4)-230317*a(n-5)+681084*a(n-6)+1237146*a(n-7)-4665436*a(n-8)+3729450*a(n-9)-1401052*a(n-10)+1331088*a(n-11)-1754064*a(n-12)+3484296*a(n-13)-2993760*a(n-14)+680400*a(n-15)

Example

Some solutions for 6X4
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..1..0..0..1....2..0..0..1....0..0..0..1....2..0..0..1....2..0..0..1
..2..1..1..0....1..2..1..0....0..1..1..0....0..0..2..0....1..2..1..0
..0..1..2..1....2..0..0..2....0..1..1..0....0..2..2..0....2..1..2..1
..0..1..0..2....1..1..0..0....1..0..2..0....0..2..1..2....0..0..0..0

Crossrefs

Sequence in context: A178973 A259248 A238519 * A115487 A210894 A145699

Adjacent sequences: A185881 A185882 A185883 * A185885 A185886 A185887

Keyword

nonn

Author

R. H. Hardin Feb 05 2011

Status

approved