A032203 Number of series-reduced planted compound windmills with n leaves.

1, 1, 2, 5, 12, 36, 104, 331, 1062, 3519, 11809, 40327, 139066, 484698, 1702819, 6026452, 21460248, 76846950, 276524978, 999423375, 3626370269, 13205135288, 48241233346, 176757275833, 649399348322, 2391817886703

Offset: 1

Author

Christian G. Bower

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..200
• Index entries for sequences related to mobiles
• INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 79

Programs

PARI

CIK(p,n)={sum(d=1, n, eulerphi(d)/d*log(subst(1/(1+O(x*x^(n\d))-p), x, x^d)))}
seq(n)={my(p=x); for(i=2, n, p+=x^i*polcoeff(CIK(p,i),i)); Vecrev(p/x)} \\ Andrew Howroyd, Jun 21 2018

Formula

Doubles (index 2+) under "CIK" (necklace, indistinct, unlabeled) transform.