The number of boundary twigs for complete binary twigs. A twig is a vertex with one edge on the boundary and only one other descendant.

A228403

The number of boundary twigs for complete binary twigs. A twig is a vertex with one edge on the boundary and only one other descendant.

Terms

    a(0) =1a(1) =4a(2) =10a(3) =28a(4) =84a(5) =264a(6) =858a(7) =2860a(8) =9724a(9) =33592a(10) =117572a(11) =416024a(12) =1485800a(13) =5348880a(14) =19389690a(15) =70715340a(16) =259289580a(17) =955277400a(18) =3534526380a(19) =13128240840a(20) =48932534040a(21) =182965127280a(22) =686119227300

External references