Number of rooted unicursal planar maps with n edges and exactly one vertex of valency 1 (unicursal means that exactly two vertices are of odd valency; there is an Eulerian path).

A069722

Number of rooted unicursal planar maps with n edges and exactly one vertex of valency 1 (unicursal means that exactly two vertices are of odd valency; there is an Eulerian path).

Terms

    a(0) =0a(1) =4a(2) =24a(3) =160a(4) =1120a(5) =8064a(6) =59136a(7) =439296a(8) =3294720a(9) =24893440a(10) =189190144a(11) =1444724736a(12) =11076222976a(13) =85201715200a(14) =657270374400

External references