A186881 - OEIS

A186881

T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock

262144, 2428, 2428, 19236, 421, 19236, 46583, 1201, 1201, 46583, 104701, 6829, 6712, 6829, 104701, 186096, 14221, 20152, 20152, 14221, 186096, 277659, 18517, 28984, 79096, 28984, 18517, 277659, 322910, 21661, 32992, 100600, 100600, 32992, 21661

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Table starts

.262144..2428..19236..46583.104701.186096..277659..322910..569446..975469

...2428...421...1201...6829..14221..18517...21661...25381...34645...64384

..19236..1201...6712..20152..28984..32992...37576...46624...73744..138808

..46583..6829..20152..79096.100600.108640..121144..148048..208576..364504

.104701.14221..28984.100600.214264.230224..260584..310528..410080..683224

.186096.18517..32992.108640.230224.287368..338176..414184..568744..927136

.277659.21661..37576.121144.260584.338176..443560..571984..798832.1272712

.322910.25381..46624.148048.310528.414184..571984..801208.1130584.1842208

.569446.34645..73744.208576.410080.568744..798832.1130584.1845448.2954656

.975469.64384.138808.364504.683224.927136.1272712.1842208.2954656.6154456

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..1402

FORMULA

Empirical, for all columns: a(n)=2*a(n-1)-a(n-2)+3*a(n-3)-6*a(n-4)+3*a(n-5)+3*a(n-6)-3*a(n-7) for n>20,10,11,12,13,14,15,16 respectively for row=1..8

EXAMPLE

Some solutions for 5X4

..0..0..0..2....0..0..1..1....0..0..0..0....1..0..0..0....3..3..3..3

..0..0..0..0....0..0..0..3....0..0..0..0....0..0..0..3....0..0..0..0

..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

..3..0..0..0....0..0..0..0....1..0..0..0....0..0..0..0....0..0..0..0

..3..3..0..0....3..0..0..0....3..0..0..0....2..0..0..0....2..2..2..2

CROSSREFS

Sequence in context: A022534 A069393 A186872 * A186873 A018867 A057445

Adjacent sequences: A186878 A186879 A186880 * A186882 A186883 A186884

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Feb 28 2011

STATUS

approved