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A032290
Number of dyslexic rooted compound windmills with n nodes and leaves of 2 colors.
1
2, 2, 5, 13, 38, 115, 377, 1267, 4446, 15970, 58741, 219765, 834779, 3208732, 12461304, 48809233, 192596729, 764814458, 3054101548, 12255774481, 49396159564, 199867069373, 811554088996, 3305812070784
OFFSET
1,1
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=2+DIK(x*p, i)); Vec(p)} \\ Andrew Howroyd, Jun 20 2018
CROSSREFS
Sequence in context: A355863 A029856 A072898 * A032201 A268180 A268003
KEYWORD
nonn
STATUS
approved