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A339232
Total number of interior vertices in the multigraphs of all oriented series-parallel networks with n edges.
2
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
1,3
COMMENTS
See A339231 for additional details.
FORMULA
a(n) = Sum_{k=1..n-1} k*A339231(n,k).
PROG
(PARI) \\ See A339231 for VertexWeighted.
seq(n)={subst(deriv(VertexWeighted(n, y)), y, 1)}
CROSSREFS
Sequence in context: A181331 A268400 A364754 * A196489 A049674 A077277
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Nov 29 2020
STATUS
approved