Number of rooted unicursal planar maps with n edges and no vertices of valency 1 (unicursal means that exactly two vertices are of odd valency; there is an Eulerian path).
A069721
Number of rooted unicursal planar maps with n edges and no vertices of valency 1 (unicursal means that exactly two vertices are of odd valency; there is an Eulerian path).
Terms
- a(0) =0a(1) =0a(2) =4a(3) =40a(4) =336a(5) =2688a(6) =21120a(7) =164736a(8) =1281280a(9) =9957376a(10) =77395968a(11) =601968640a(12) =4686094336a(13) =36515020800a(14) =284817162240
External references
- oeis: A069721