A058494 - OEIS

%I #8 May 19 2021 00:11:34

%S 0,0,1,6,20,74,245,845

%N Total number of interior nodes in all essentially parallel series-parallel networks with n unlabeled edges, multiple edges allowed.

%D J. W. Moon, Some enumerative results on series-parallel networks, Annals Discrete Math., 33 (1987), 199-226 (the sequence I_p(n)*p_pi).

%H <a href="/index/Mo#Moon87">Index entries for sequences mentioned in Moon (1987)</a>

%F Reference gives g.f.

%Y Cf. A058488, A058495.

%K nonn,nice,more

%O 0,4

%A _N. J. A. Sloane_, Dec 20 2000