|
|
A262472
|
|
T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with each row divisible by 3 and each column divisible by 5, read as a binary number with top and left being the most significant bits.
|
|
13
|
|
|
1, 1, 2, 1, 3, 4, 1, 6, 9, 7, 1, 11, 36, 17, 13, 1, 22, 121, 115, 37, 26, 1, 43, 484, 457, 469, 107, 52, 1, 86, 1849, 3055, 2413, 2622, 321, 103, 1, 171, 7396, 16081, 30229, 22907, 15732, 865, 205, 1, 342, 29241, 107731, 234421, 552430, 239281, 85723, 2449, 410, 1
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
COMMENTS
|
Table starts
...1....1.......1.........1...........1............1............1............1
...2....3.......6........11..........22...........43...........86..........171
...4....9......36.......121.........484.........1849.........7396........29241
...7...17.....115.......457........3055........16081.......107731.......655001
..13...37.....469......2413.......30229.......234421......2924245.....29005981
..26..107....2622.....22907......552430......8080915....194647694...3858564731
..52..321...15732....239281....11489332....326748241..15659602612.630055962801
.103..865...85723...2028469...198237391..10190636521.997197229531
.205.2449..494605..19072681..3805146805.367750753321
.410.7299.2942190.195594107.77803476910
|
|
LINKS
|
|
|
FORMULA
|
Empirical for column k:
k=1: a(n) = 3*a(n-1) -3*a(n-2) +3*a(n-3) -2*a(n-4)
k=2: [order 8]
k=3: [order 15]
k=4: [order 73]
Empirical for row n:
n=1: a(n) = a(n-1)
n=2: a(n) = 2*a(n-1) +a(n-2) -2*a(n-3)
n=3: a(n) = 4*a(n-1) +5*a(n-2) -20*a(n-3) -4*a(n-4) +16*a(n-5)
n=4: [order 13]
n=5: [order 33]
n=6: [order 67]
|
|
EXAMPLE
|
Some solutions for n=4 k=4
..0..0..0..0..0....0..0..0..0..0....0..1..1..0..0....0..1..0..0..1
..0..1..0..0..1....0..1..1..0..0....0..1..0..0..1....0..0..0..1..1
..0..0..0..0..0....0..1..0..0..1....0..1..1..1..1....0..1..0..0..1
..0..1..0..0..1....0..1..1..0..0....0..1..0..0..1....0..0..0..1..1
..0..0..0..0..0....0..1..0..0..1....0..0..0..1..1....0..0..0..0..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|