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A032188 Number of labeled series-reduced mobiles (circular rooted trees) with n leaves (root has degree 0 or >=2). +0
9
1, 1, 5, 41, 469, 6889, 123605, 2620169, 64074901, 1775623081, 54989743445, 1882140936521, 70552399533589, 2874543652787689, 126484802362553045, 5977683917752887689, 301983995802099667861, 16239818347465293071401 (list; graph; listen)
OFFSET

1,3

LINKS

Index entries for sequences related to mobiles

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 89

FORMULA

Doubles (index 2+) under "CIJ" (necklace, indistinct, labeled) transform.

E.g.f. A(x) satisfies ln(1-A(x))+2*A(x)-x = 0. - Vladeta Jovovic (vladeta(AT)eunet.rs), Dec 06 2002

With offset 0, second Eulerian transform of the powers of 2 [A000079]. See A001147 for definition of SET. - Ross La Haye (rlahaye(AT)new.rr.com), Feb 14 2005

MAPLE

Order := 20; t1 := solve(series((ln(1-A)+2*A), A)=x, A); A000311 := n->n!*coeff(t1, x, n);

MATHEMATICA

For[y=x+O[x]^21; oldy=0, y=!=oldy, oldy=y; y=((1-y)Log[1-y]+x*y+y-x)/(2y-1), Null]; Table[n!Coefficient[y, x, n], {n, 1, 20}]

CROSSREFS

Sequence in context: A047735 A096364 A049119 this_sequence A143415 A056545 A009755

Adjacent sequences: A032185 A032186 A032187 this_sequence A032189 A032190 A032191

KEYWORD

nonn,eigen

AUTHOR

Christian G. Bower (bowerc(AT)usa.net)

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Last modified March 19 01:26 EDT 2010. Contains 173632 sequences.


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