|
|
A280284
|
|
T(n,k)=Number of nXk 0..2 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
|
|
6
|
|
|
0, 0, 0, 1, 4, 1, 2, 46, 46, 2, 8, 384, 996, 384, 8, 28, 2894, 16860, 16860, 2894, 28, 94, 20444, 259040, 592416, 259040, 20444, 94, 304, 138944, 3753846, 18844474, 18844474, 3753846, 138944, 304, 960, 918744, 52433492, 566131860, 1240628942
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,5
|
|
COMMENTS
|
Table starts
....0........0............1..............2...............8...............28
....0........4...........46............384............2894............20444
....1.......46..........996..........16860..........259040..........3753846
....2......384........16860.........592416........18844474........566131860
....8.....2894.......259040.......18844474......1240628942......77217209188
...28....20444......3753846......566131860.....77217209188....9962925424456
...94...138944.....52433492....16393550046...4633270354464.1239330073038612
..304...918744....713549156...462579750172.270955366695864
..960..5954690...9525564453.12805032188772
.2976.38005496.125290653912
|
|
LINKS
|
|
|
FORMULA
|
Empirical for column k:
k=1: a(n) = 4*a(n-1) -8*a(n-3) -4*a(n-4) for n>7
k=2: [order 8]
k=3: [order 24] for n>25
|
|
EXAMPLE
|
Some solutions for n=3 k=4
..0..1..0..2. .0..1..1..0. .0..0..1..2. .0..0..1..1. .0..1..2..0
..2..0..1..2. .2..0..2..0. .2..1..2..2. .1..0..2..0. .2..2..0..1
..2..0..0..1. .0..2..2..1. .0..2..1..1. .2..1..1..2. .0..1..0..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|