Numerator of J(n) = A000356(n)/A000309(n) (average number of 4-colorings of rank 0 in a rooted nonseparable map which is trivalent and has 2n nodes).

A097872

Numerator of J(n) = A000356(n)/A000309(n) (average number of 4-colorings of rank 0 in a rooted nonseparable map which is trivalent and has 2n nodes).

Terms

    a(0) =1a(1) =5a(2) =35a(3) =147a(4) =99a(5) =4719a(6) =102245a(7) =158015a(8) =71383a(9) =9493939a(10) =117578783a(11) =81161825a(12) =192225375a(13) =10034164575a(14) =176876744175a(15) =874129996575a(16) =506075261175

External references