A339232 Total number of interior vertices in the multigraphs of all oriented series-parallel networks with n edges.

0, 1, 5, 23, 99, 433, 1880, 8238, 36202, 159898, 708517, 3150128, 14042620, 62751693, 280997846, 1260635337, 5664870696, 25493707908, 114882350739, 518318733052, 2341079272919, 10584488664085, 47898510357544, 216940538748652, 983326680302665, 4460343301915203

Offset: 1

Author

Andrew Howroyd, Nov 29 2020

Keywords

• nonn

Comments

See A339231 for additional details.

Crossrefs

Cf. A003430, A339231.

Programs

PARI

\\ See A339231 for VertexWeighted.
seq(n)={subst(deriv(VertexWeighted(n,y)), y, 1)}

Formula

a(n) = Sum_{k=1..n-1} k*A339231(n,k).