|
Search: id:A132339
|
|
|
| A132339 |
|
Array read by antidiagonals: see formula line for definition. |
|
+0
6
|
|
| 1, -1, -1, 0, 2, 0, 0, -2, -2, 0, 0, 2, 10, 2, 0, 0, -2, -28, -28, -2, 0, 0, 2, 60, 168, 60, 2, 0, 0, -2, -110, -660, -660, -110, -2, 0
(list; table; graph; listen)
|
|
|
OFFSET
|
0,5
|
|
|
REFERENCES
|
G. Kreweras, Sur une classe de problemes de denombrement lies au treillis des partitions des entiers, Cahiers du Bureau Universitaire de Recherche Op\'{e}rationnelle, Institut de Statistique, Universit\'{e} de Paris, 6 (1965), circa p. 82.
|
|
FORMULA
|
A(n,k) = 2(-1)^(h+k) (h+k-1)! (2h+2k-3)! / ( h! k! (2h-1)! (2k-1)! ), h >= 0, k >= 0.
|
|
EXAMPLE
|
Array begins:
1 -1 0 0 0 0 0 0 ...
-1 2 -2 2 -2 2 -2 2 ...
0 -2 10 -28 60 -110 ...
0 2 -28 168 -660 2002 ...
...
|
|
CROSSREFS
|
Rows give A006331-A006334. Main diagonal is A132341.
Sequence in context: A033985 A122071 A099766 this_sequence A137676 A144734 A029361
Adjacent sequences: A132336 A132337 A132338 this_sequence A132340 A132341 A132342
|
|
KEYWORD
|
sign,tabl,easy,more
|
|
AUTHOR
|
njas, Nov 08 2007
|
|
|
Search completed in 0.002 seconds
|
