Number of planar rooted trees with n nodes and tricolored end nodes.

A047891

Number of planar rooted trees with n nodes and tricolored end nodes.

Terms

    a(0) =1a(1) =3a(2) =12a(3) =57a(4) =300a(5) =1686a(6) =9912a(7) =60213a(8) =374988a(9) =2381322a(10) =15361896a(11) =100389306a(12) =663180024a(13) =4421490924a(14) =29712558576a(15) =201046204173

External references