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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, 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
OFFSET
1,4
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
KEYWORD
nonn
STATUS
approved