a(0)=0; for n>0, a(n) is the number of rooted 4-regular maps on the torus having n vertices.

A322914

a(0)=0; for n>0, a(n) is the number of rooted 4-regular maps on the torus having n vertices.

Terms

    a(0) =0a(1) =1a(2) =15a(3) =198a(4) =2511a(5) =31266a(6) =385398a(7) =4721004a(8) =57590271a(9) =700465482a(10) =8501284530a(11) =103007201364

External references