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A057505 Permutation of natural numbers induced by the automorphism DonagheysM (or DeepRotateTriangularization) acting on the parenthesizations encoded by A014486. +0
48
0, 1, 3, 2, 8, 7, 5, 6, 4, 22, 21, 18, 20, 17, 13, 12, 15, 19, 16, 10, 11, 14, 9, 64, 63, 59, 62, 58, 50, 49, 55, 61, 57, 46, 48, 54, 45, 36, 35, 32, 34, 31, 41, 40, 52, 60, 56, 43, 47, 53, 44, 27, 26, 29, 33, 30, 38, 39, 51, 42, 24, 25, 28, 37, 23, 196, 195, 190, 194, 189 (list; graph; listen)
OFFSET

0,3

COMMENT

This is equivalent to map M given by Donaghey on page 81 of his paper "Automorphisms on ...", and also equivalent to the transformation procedure depicted in the picture (23) of Donaghey-Shapiro paper.

This can be also considered as a "deeply recursive" variant of A057501 or a recursive variant of A057161.

REFERENCES

R. Donaghey, Automorphisms on Catalan trees and bracketing, J. Combin. Theory, Series B, 29 (1980), 75-90.

R. Donaghey & L. W. Shapiro, Motzkin numbers, J. Combin. Theory, Series A, 23 (1977), 291-301.

LINKS

A. Karttunen, Gatomorphisms (Includes the complete Scheme source for computing this sequence)

Index entries for sequences that are permutations of the natural numbers

MAPLE

map(CatalanRankGlobal, map(DonagheysM, A014486)); or map(CatalanRankGlobal, map(DeepRotateTriangularization, A014486));

DonagheysM := n -> pars2binexp(DonagheysMP(binexp2pars(n)));

DonagheysMP := h -> `if`((0 = nops(h)), h, [op(DonagheysMP(car(h))), DonagheysMP(cdr(h))]);

DeepRotateTriangularization := proc(nn) local n, s, z, w; n := binrev(nn); z := 0; w := 0; while(1 = (n mod 2)) do s := DeepRotateTriangularization(BinTreeRightBranch(n))*2; z := z + (2^w)*s; w := w + binwidth(s); z := z + (2^w); w := w + 1; n := floor(n/2); od; RETURN(z); end;

PROGRAM

(Two alternative Scheme functions implementing this automorphism on list-structures:)

(define (DonagheysM a) (cond ((null? a) a) (else (append (DonagheysM (car a)) (list (DonagheysM (cdr a)))))))

(define (DeepRotateTriangularization bt) (let loop ((lt bt) (nt (list))) (cond ((not (pair? lt)) nt) (else (loop (car lt) (cons (DeepRotateTriangularization (cdr lt)) nt))))))

CROSSREFS

Inverse permutation: A057506, and also its car/cdr-flipped conjugate, i.e. A0057505(n) = A057163(A057506(A057163(n))). Composition of A057163 & A057164, i.e. A057505(n) = A057164(A057163(n)).

The 2nd, 3rd, 4th, 5th and 6th "power": A071661, A071663, A071665, A071667, A071669.

Cycle counts: A057507. Maximum cycle lengths: A057545. LCM's of all cycles: A060114. See A057501 for other Maple procedures.

Row 17 of table A122288.

Sequence in context: A130362 A085173 A071668 this_sequence A122357 A122298 A122337

Adjacent sequences: A057502 A057503 A057504 this_sequence A057506 A057507 A057508

KEYWORD

nonn

AUTHOR

Antti Karttunen Sep 03 2000

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Last modified November 21 14:49 EST 2008. Contains 150807 sequences.


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