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A339232
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Total number of interior vertices in the multigraphs of all oriented series-parallel networks with n edges.
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2
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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
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OFFSET
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1,3
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COMMENTS
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See A339231 for additional details.
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LINKS
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FORMULA
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a(n) = Sum_{k=1..n-1} k*A339231(n,k).
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PROG
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(PARI) \\ See A339231 for VertexWeighted.
seq(n)={subst(deriv(VertexWeighted(n, y)), y, 1)}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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