|
| |
|
|
A051485
|
|
Number of double nodes (exactly two nodes on that level) for all Motzkin paths of length n.
|
|
0
| |
|
|
0, 1, 1, 2, 6, 14, 32, 74, 180, 457, 1195, 3177, 8526, 23018, 62441, 170153
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,4
|
|
|
REFERENCES
| Wen-jin Woan, "Unilevel Points Via Generating Functions", preprint, 1999.
|
|
|
EXAMPLE
| Of the 9 Motzkin paths of length 4 the following 5 have a total of 6 double nodes:
|1......|
|2../\..|3..__..|2.._...|2..._..|2......|
|2./..\.|2./..\.|3./.\_.|3._/.\.|3./\/\.|
|
|
|
CROSSREFS
| Sequence in context: A074878 A065495 A131352 * A077999 A110524 A083404
Adjacent sequences: A051482 A051483 A051484 * A051486 A051487 A051488
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Wen-jin Woan (wwoan(AT)howard.edu)
|
|
|
EXTENSIONS
| Edited by Michael Somos, Sep 29, 2003
|
| |
|
|
