Number of unlabeled lone-child-avoiding rooted trees with n vertices and more than two branches (of the root).

A331488

Number of unlabeled lone-child-avoiding rooted trees with n vertices and more than two branches (of the root).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =1a(5) =2a(6) =3a(7) =6a(8) =10a(9) =20a(10) =36a(11) =70a(12) =134a(13) =263a(14) =513a(15) =1022a(16) =2030a(17) =4076a(18) =8203a(19) =16614a(20) =33738a(21) =68833a(22) =140796a(23) =288989a(24) =594621a(25) =1226781a(26) =2536532a(27) =5256303a(28) =10913196a(29) =22700682

External references