Number of rooted planar binary unlabeled trees with n leaves and caterpillar index >= 3.

A214198

Number of rooted planar binary unlabeled trees with n leaves and caterpillar index >= 3.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =2a(4) =4a(5) =12a(6) =36a(7) =116a(8) =384a(9) =1304a(10) =4504a(11) =15772a(12) =55832a(13) =199432a(14) =717816a(15) =2600680a(16) =9476800a(17) =34710000a(18) =127712560a(19) =471851180a(20) =1749864920a(21) =6511643720a(22) =24307501720a(23) =91000873560a(24) =341594374400

External references