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A032129
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Number of dyslexic rooted planar trees with n nodes.
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1
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1, 1, 2, 4, 9, 21, 55, 146, 413, 1194, 3553, 10756, 33134, 103273, 325484, 1034734, 3314870, 10688513, 34662777, 112976023, 369876832, 1215811262, 4010932603, 13275356936, 44070010202, 146698487202, 489550622528, 1637472527602, 5488829461525, 18435194140301
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OFFSET
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1,3
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LINKS
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FORMULA
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"DIK" (bracelet, indistinct, unlabeled) transform of A032128 (shifted right one place).
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PROG
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(PARI)
BIK(p)={(1/(1-p) + (1+p)/subst(1-p, x, x^2))/2}
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-1, p=BIK(x*p)); Vec(1+DIK(x*p, n))} \\ Andrew Howroyd, Aug 30 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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