A032143 - OEIS

A032143

Number of compound rooted windmills with n nodes where any 2 submills extending from the same node are of different sizes.

1, 1, 1, 2, 3, 6, 13, 28, 60, 135, 316, 731, 1735, 4133, 9937, 24133, 58820, 144227, 355966, 881868, 2192529, 5479166, 13717843, 34474835, 86848986, 219454215, 555371300, 1409893698, 3583579216, 9130512970, 23294809707

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OFFSET

1,4

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

Index entries for sequences related to mobiles

FORMULA

Shifts left under "CFK" (necklace, size, unlabeled) transform

PROG

(PARI)

CFK(v)={apply(p->subst(serlaplace(p/y), y, 1), Vec(-1+prod(k=1, #v, 1 + v[k]*x^k*y + O(x*x^#v)), -#v))}

seq(n)={my(v=[1]); for(i=2, n, v=concat([1], CFK(v))); v} \\ Andrew Howroyd, Sep 20 2018

CROSSREFS

Sequence in context: A324770 A075853 A132045 * A032160 A089735 A316694

Adjacent sequences: A032140 A032141 A032142 * A032144 A032145 A032146

KEYWORD

nonn

AUTHOR

Christian G. Bower

STATUS

approved