Another 3-way generalization of series-parallel networks with n unlabeled edges.
A058540
Another 3-way generalization of series-parallel networks with n unlabeled edges.
Terms
- a(0) =0a(1) =1a(2) =3a(3) =9a(4) =36a(5) =144a(6) =651a(7) =3015a(8) =14634a(9) =72654a(10) =369063a(11) =1904985a(12) =9971889a(13) =52788393a(14) =282161025a(15) =1520597895a(16) =8253281871a(17) =45075359277a(18) =247534382298
External references
- oeis: A058540