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A108532
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Number of asymmetric mobiles (cycle rooted trees) with n nodes and 2-colored internal (non-leaf) nodes.
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3
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1, 2, 4, 12, 38, 136, 490, 1852, 7108, 27880, 110892, 447060, 1821252, 7489732, 31045350, 129587996, 544228664, 2298008824, 9750218012, 41548438040, 177740526076, 763046178960, 3286318131646, 14195239150556, 61481540391722
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OFFSET
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1,2
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LINKS
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FORMULA
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Shifts left and halves under CHK transform.
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PROG
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(PARI)
CHK(p, n)={sum(d=1, n, moebius(d)/d*log(subst(1/(1+O(x*x^(n\d))-p), x, x^d)))}
seq(n)={my(p=O(1)); for(i=1, n, p=1+2*CHK(x*p, i)); Vec(p)} \\ Andrew Howroyd, Jun 20 2018
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CROSSREFS
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KEYWORD
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nonn,eigen
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AUTHOR
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STATUS
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approved
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