Number of lobsters with n nodes that are not caterpillars.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =3a(6) =11a(7) =33a(8) =95a(9) =260a(10) =696a(11) =1816a(12) =4659a(13) =11795a(14) =29520a(15) =73267a(16) =180485a(17) =442157a(18) =1077856a(19) =2617726a(20) =6336551a(21) =15299287a(22) =36857178a(23) =88635225a(24) =212829307a(25) =510416549a(26) =1222826994a(27) =2927083468a(28) =7001510693a(29) =16737477645