A072092 Permutation of natural numbers induced by the automorphism car_robr_car! acting on the parenthesizations encoded by A014486.

0, 1, 3, 2, 7, 8, 4, 6, 5, 17, 18, 20, 21, 22, 9, 10, 14, 19, 16, 11, 12, 15, 13, 45, 46, 48, 49, 50, 54, 55, 57, 58, 59, 61, 62, 63, 64, 23, 24, 25, 26, 27, 37, 38, 51, 56, 60, 42, 44, 53, 47, 28, 29, 30, 31, 32, 39, 40, 43, 52, 33, 34, 35, 41, 36, 129, 130, 132, 133, 134

Offset

0,3

Links

Table of n, a(n) for n=0..69.

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

Index entries for sequences that are permutations of the natural numbers

Prog

(Scheme function implementing this automorphism on list-structures:)
(define (car_robr_car! s) (cond ((not (pair? s))) ((not (pair? (car s))) (swap! s)) (else (car_robr_car! (car s)) (robr! s) (car_robr_car! (car s)))) s)
(define (robr! s) (let ((ex-cdr (cdr s))) (set-cdr! s (caar s)) (set-car! (car s) ex-cdr) (swap! (car s)) (swap! s) s))
(define (swap! s) (let ((ex-car (car s))) (set-car! s (cdr s)) (set-cdr! s ex-car) s))

Crossrefs

Inverse permutation: A072093. The car/cdr-flipped conjugate of A072095, i.e. A072092(n) = A057163(A072095(A057163(n))). Cf. also A071655-A071660, A072090-A072091.

Sequence in context: A130926 A069774 A089861 * A071659 A130931 A130962

Adjacent sequences: A072089 A072090 A072091 * A072093 A072094 A072095

Keyword

nonn

Author

Antti Karttunen, Jun 25 2002

Status

approved