|
|
A356697
|
|
Number of Catalan words of length n avoiding the pattern 0000.
|
|
3
|
|
|
1, 1, 2, 5, 13, 36, 101, 280, 788, 2212, 6186, 17384, 48755, 136649, 383584, 1075734, 3016924, 8464693, 23740844, 66592246, 186807727, 523973400, 1469769653, 4122833303, 11564436141, 32438795011, 90992182917, 255234015580, 715941436278, 2008237780651
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
FORMULA
|
G.f.: -(3*x^5-9*x^3-2*x^2+1)/((x-1)*(x^5-5*x^4-12*x^3-3*x^2+1)).
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|