Number of rooted bicubic maps: a(n) = (8*n-4)*a(n-1)/(n+2) for n >= 2, a(0) = a(1) = 1.

A000257

Number of rooted bicubic maps: a(n) = (8*n-4)*a(n-1)/(n+2) for n >= 2, a(0) = a(1) = 1.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =12a(4) =56a(5) =288a(6) =1584a(7) =9152a(8) =54912a(9) =339456a(10) =2149888a(11) =13891584a(12) =91287552a(13) =608583680a(14) =4107939840a(15) =28030648320a(16) =193100021760

External references