A032129 Number of dyslexic rooted planar trees with n nodes.

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

Offset

1,3

Links

Andrew Howroyd, Table of n, a(n) for n = 1..200

C. G. Bower, Transforms (2)

Index entries for sequences related to rooted trees

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: A378516 A106219 A198304 * A304914 A005217 A148072

Adjacent sequences: A032126 A032127 A032128 * A032130 A032131 A032132

Keyword

nonn

Author

Christian G. Bower

Extensions

Terms a(28) and beyond from Andrew Howroyd, Aug 30 2018

Status

approved