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A032289 Number of dyslexic rooted compound windmills with n nodes. 2
1, 1, 2, 4, 9, 20, 49, 119, 305, 790, 2100, 5648, 15449, 42664, 119128, 335310, 951119, 2714974, 7795211, 22493655, 65202995, 189767806, 554326057, 1624572250, 4775504516, 14076385819, 41596613660, 123206155126 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
Shifts left under "DIK" (bracelet, indistinct, unlabeled) transform.
PROG
(PARI)
DIK(p, n)={(sum(d=1, n, eulerphi(d)/d*log(subst(1/(1+O(x*x^(n\d))-p), x, x^d))) + ((1+p)^2/(1-subst(p, x, x^2))-1)/2)/2}
seq(n)={my(p=O(1)); for(i=1, n, p=1+DIK(x*p, i)); Vec(p)} \\ Andrew Howroyd, Jun 20 2018
CROSSREFS
Cf. A038038.
Sequence in context: A289971 A093637 A068051 * A006648 A128496 A134955
KEYWORD
nonn,eigen
AUTHOR
STATUS
approved

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Last modified May 17 06:15 EDT 2024. Contains 372579 sequences. (Running on oeis4.)