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A032161 Number of rooted compound windmills with n nodes and leaves of 2 colors where any 2 submills extending from the same node are different. 1
2, 2, 3, 7, 18, 48, 145, 444, 1393, 4507, 14759, 49142, 165317, 562091, 1925899, 6647608, 23092972, 80660663, 283138682, 998248096, 3533524793, 12552572322, 44737515682, 159919954982, 573214555207, 2059779884427 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

C. G. Bower, Transforms (2)

Index entries for sequences related to mobiles

FORMULA

Shifts left under "CGK" (necklace, element, unlabeled) transform.

PROG

(PARI)

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

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

CROSSREFS

Sequence in context: A128776 A117387 A113842 * A265801 A098738 A291742

Adjacent sequences:  A032158 A032159 A032160 * A032162 A032163 A032164

KEYWORD

nonn

AUTHOR

Christian G. Bower

STATUS

approved

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Last modified October 18 07:00 EDT 2018. Contains 316307 sequences. (Running on oeis4.)