A238046 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median minus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one

81, 340, 340, 1440, 1944, 1440, 6064, 10812, 10812, 6064, 25948, 61668, 81524, 61668, 25948, 109200, 352180, 621780, 621780, 352180, 109200, 466296, 1999804, 4837484, 6698520, 4837484, 1999804, 466296, 1962720, 11359816, 36440340, 70363916

Offset

1,1

Comments

Table starts

.......81........340.........1440..........6064...........25948

......340.......1944........10812.........61668..........352180

.....1440......10812........81524........621780.........4837484

.....6064......61668.......621780.......6698520........70363916

....25948.....352180......4837484......70363916......1021660750

...109200....1999804.....36440340.....735878108.....14397005860

...466296...11359816....282305082....7744640808....209192156822

..1962720...64650988...2134998732...81468910084...2964129769048

..8385248..367695852..16538701324..855621962264..42974757198114

.35292928.2090439976.124970610892.8992624643448.608837111985680

Links

R. H. Hardin, Table of n, a(n) for n = 1..144

Formula

Empirical for column k:

k=1: a(n) = 8*a(n-2) +152*a(n-4) +472*a(n-6) +384*a(n-8)

k=2: [order 13]

k=3: [order 50]

Example

Some solutions for n=3 k=4
..0..1..1..0..2....0..0..2..2..1....0..1..1..1..0....0..0..2..0..1
..0..1..0..2..0....0..1..2..0..0....0..1..2..2..1....0..1..0..2..0
..0..0..2..0..1....0..2..2..1..0....1..1..2..0..0....0..2..1..0..0
..1..1..1..2..1....1..1..1..0..2....2..2..2..1..0....1..1..2..1..2

Crossrefs

Sequence in context: A236902 A236895 A237965 * A237958 A238039 A232284

Adjacent sequences: A238043 A238044 A238045 * A238047 A238048 A238049

Keyword

nonn,tabl

Author

R. H. Hardin, Feb 17 2014

Status

approved