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A032203
Number of series-reduced planted compound windmills with n leaves.
2
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
1,3
FORMULA
Doubles (index 2+) under "CIK" (necklace, indistinct, unlabeled) transform.
PROG
(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
CROSSREFS
Sequence in context: A225798 A303204 A333411 * A197444 A094717 A323933
KEYWORD
nonn
STATUS
approved