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Andrew Howroyd, <a href="/A032188/b032188.txt">Table of n, a(n) for n = 1..200</a>
E.g.f: series reversion of 2*x + log(1-x). - Andrew Howroyd, Sep 19 2018
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a(n) = A032034(n)/2. - Alois P. Heinz, Jul 04 2018
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Number of labeled series-reduced mobiles (circular rooted trees) with n leaves (root has degree 0 or >= 2).
The integral from 0 to infinity w.r.t. w of exp(-2w)(1-z*w)^(-1/z) gives an o.g.f. for the series with offset 0. Consequently, a(n)= sum(j=1 to infinity): St1d(n,j)/(2^(n+j-1)) where St1d(n,j) is the j-th element of the n-th diagonal of A132393 with offset=1; e.g. , a(3)= 5 = 0/2^3 + 2/2^4 + 11/2^5 + 35/2^6 + 85/2^7 + ... . - Tom Copeland, Sep 15 2011
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... 1a....... 1a....... 1b........ 1a........ 1b....
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... 2a..... 2... 3.... 2.... 3.... 3.... 2.... 3.... 2..
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...3...........................................
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