|
| |
|
|
A203734
|
|
Number of (n+1)X2 0..3 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) nondecreasing in column and row directions, respectively
|
|
0
|
|
|
|
90, 499, 2166, 8667, 31942, 111916, 376415, 1228141, 3911718, 12225055, 37629475, 114415963, 344453875, 1028640925, 3051602949, 9004181108, 26450597561, 77418965194, 225924263865, 657679624225, 1910701827288, 5541861127364
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
|
|
|
LINKS
|
|
|
|
FORMULA
|
Empirical: a(n) = 10*a(n-1) -35*a(n-2) +35*a(n-3) +72*a(n-4) -178*a(n-5) +7*a(n-6) +259*a(n-7) -123*a(n-8) -182*a(n-9) +125*a(n-10) +68*a(n-11) -56*a(n-12) -13*a(n-13) +12*a(n-14) +a(n-15) -a(n-16)
|
|
|
EXAMPLE
|
Some solutions for n=4
..0..3....2..2....0..1....0..2....2..0....1..3....3..3....0..1....1..0....2..0
..0..3....1..3....0..1....1..3....0..2....1..3....3..3....3..2....0..1....0..2
..1..2....1..3....1..1....2..2....1..2....3..1....3..3....2..3....0..3....1..1
..1..3....2..2....3..3....1..3....3..2....1..3....3..3....3..2....1..2....3..3
..3..3....1..3....3..3....2..2....2..3....1..3....3..3....2..3....1..2....3..3
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
