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 A032129 Number of dyslexic rooted planar trees with n nodes. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..200 C. G. Bower, Transforms (2) FORMULA "DIK" (bracelet, indistinct, unlabeled) transform of A032128 (shifted right one place). PROG (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 CROSSREFS Cf. A032128. Sequence in context: A063026 A106219 A198304 * A304914 A005217 A148072 Adjacent sequences:  A032126 A032127 A032128 * A032130 A032131 A032132 KEYWORD nonn AUTHOR EXTENSIONS Terms a(28) and beyond from Andrew Howroyd, Aug 30 2018 STATUS approved

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Last modified December 3 00:59 EST 2021. Contains 349445 sequences. (Running on oeis4.)