|
| |
|
|
A027302
|
|
a(n) = Sum{T(n,k)*T(n,k+1)}, 0<=k<=[ (n-1)/2 ], T given by A008315.
|
|
1
| |
|
|
1, 2, 9, 24, 95, 286, 1099, 3536, 13479, 45220, 172150, 594320, 2265003, 7983990, 30487175, 109174560, 417812417, 1514797020, 5810065898, 21275014800, 81775140083, 301892460012
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| a(n) is the number of Dyck (n+2)-paths with UU spanning the midpoint. e.g. for n=2 the two Dyck 4-paths are UUDU.UDDD and UDUU.UDDD where dot marks the midpoint. [David Scambler (dscambler AT bmm.com)]
|
|
|
CROSSREFS
| Sequence in context: A122006 A200086 A143561 * A073981 A006973 A137852
Adjacent sequences: A027299 A027300 A027301 * A027303 A027304 A027305
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Clark Kimberling (ck6(AT)evansville.edu)
|
| |
|
|
