A233733 T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal.

40, 148, 148, 556, 756, 556, 2104, 3972, 3972, 2104, 7976, 21432, 29816, 21432, 7976, 30260, 115972, 233432, 233432, 115972, 30260, 114820, 631628, 1851404, 2723072, 1851404, 631628, 114820, 435720, 3435216, 14802604, 32240288, 32240288

Offset

1,1

Comments

Table starts

......40.......148.........556..........2104.............7976

.....148.......756........3972.........21432...........115972

.....556......3972.......29816........233432..........1851404

....2104.....21432......233432.......2723072.........32240288

....7976....115972.....1851404......32240288........578163016

...30260....631628....14802604.....389230764......10577526052

..114820...3435216...118695412....4696134192.....195088215888

..435720..18733728...953471940...57174669348....3616933627344

.1653488.102007004..7663964828..693181060760...67204709367712

.6274804.556289404.61629254552.8455863542400.1250516988640176

Links

R. H. Hardin, Table of n, a(n) for n = 1..220

Formula

Empirical for column k:

k=1: a(n) = 3*a(n-1) +5*a(n-2) -7*a(n-3) -2*a(n-4)

k=2: [order 12]

k=3: [order 28]

k=4: [order 84]

Example

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

Crossrefs

Sequence in context: A044372 A044753 A160148 * A233726 A100766 A189541

Adjacent sequences: A233730 A233731 A233732 * A233734 A233735 A233736

Keyword

nonn,tabl

Author

R. H. Hardin, Dec 15 2013

Status

approved