|
| |
|
|
A250693
|
|
Number of (2+1)X(n+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction
|
|
2
|
|
|
|
520, 2920, 13906, 60508, 249512, 995624, 3894542, 15061244, 57914756, 222291368, 853854042, 3287692860, 12701872800, 49262782920, 191821043814, 749801489244, 2941369935292, 11575782602248, 45685412767666, 180742482085084
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
Row 2 of A250691
|
|
|
LINKS
|
R. H. Hardin, Table of n, a(n) for n = 1..210
|
|
|
FORMULA
|
Empirical: a(n) = 20*a(n-1) -175*a(n-2) +882*a(n-3) -2835*a(n-4) +6072*a(n-5) -8777*a(n-6) +8458*a(n-7) -5204*a(n-8) +1848*a(n-9) -288*a(n-10)
|
|
|
EXAMPLE
|
Some solutions for n=4
..2..3..1..1..1....0..2..1..0..0....0..1..1..1..2....0..0..3..1..2
..1..2..0..0..0....0..2..2..2..2....0..1..1..1..3....0..0..3..1..2
..0..3..3..3..3....0..3..3..3..3....0..1..1..1..3....0..0..3..1..3
|
|
|
CROSSREFS
|
Sequence in context: A147854 A147856 A094903 * A200427 A250678 A178269
Adjacent sequences: A250690 A250691 A250692 * A250694 A250695 A250696
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
R. H. Hardin, Nov 26 2014
|
|
|
STATUS
|
approved
|
| |
|
|
