A186871 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock sum equal to exactly one or two horizontal and vertical neighbor 2X2 subblock sums.

0, 171, 171, 361, 2121, 361, 3645, 24414, 24414, 3645, 13365, 285724, 431016, 285724, 13365, 94905, 3409112, 12048996, 12048996, 3409112, 94905, 424845, 40893800, 270129432, 630235528, 270129432, 40893800, 424845, 2682129, 492154924

Offset

1,2

Comments

Table starts

.......0.......171........361........3645.......13365......94905.......424845

.....171......2121......24414......285724.....3409112...40893800....492154924

.....361.....24414.....431016....12048996...270129432.6869877312.162868019530

....3645....285724...12048996...630235528.30995088416

...13365...3409112..270129432.30995088416

...94905..40893800.6869877312

..424845.492154924

.2682129

Links

R. H. Hardin, Table of n, a(n) for n = 1..39

Example

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

Crossrefs

Column 1 is A185610

Sequence in context: A243294 A015975 A292090 * A185614 A187140 A185845

Adjacent sequences: A186868 A186869 A186870 * A186872 A186873 A186874

Keyword

nonn,tabl

Author

R. H. Hardin, Feb 27 2011

Status

approved