Number of crossing partitions of {1,2,...,n} that contain singletons.

A247494

Number of crossing partitions of {1,2,...,n} that contain singletons.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =5a(6) =45a(7) =322a(8) =2086a(9) =13092a(10) =82060a(11) =523116a(12) =3429481a(13) =23279555a(14) =164244262a(15) =1206458632a(16) =9228941572a(17) =73471779239a(18) =608000100209

External references