Number of noncrossing partitions of the n-set with some pair of singletons {i} and {j} that can be merged into {i,j} and leave the partition a noncrossing-partition.
A363449
Number of noncrossing partitions of the n-set with some pair of singletons {i} and {j} that can be merged into {i,j} and leave the partition a noncrossing-partition.
Terms
- a(0) =0a(1) =0a(2) =1a(3) =1a(4) =5a(5) =16a(6) =55a(7) =197a(8) =705a(9) =2563a(10) =9381a(11) =34563a(12) =128029a(13) =476347a(14) =1779107a(15) =6666752a(16) =25054585a(17) =94401460a(18) =356510371a(19) =1349182629a(20) =5115555725a(21) =19429832443a(22) =73916249353a(23) =281613780638
External references
- oeis: A363449