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Permutation of natural numbers induced by the Catalan bijection gma082351 acting on the parenthesizations encoded by A014486/A063171.
9

%I #6 Oct 15 2015 10:55:24

%S 0,1,2,3,4,5,8,6,7,9,10,11,12,13,19,20,21,14,15,22,16,17,18,23,24,25,

%T 26,27,28,29,30,31,32,33,34,35,36,51,52,53,54,55,56,57,58,37,38,59,39,

%U 40,41,60,61,62,42,43,63,44,45,46,64,47,48,49,50,65,66,67,68,69

%N Permutation of natural numbers induced by the Catalan bijection gma082351 acting on the parenthesizations encoded by A014486/A063171.

%H A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (with the complete Scheme source)

%H <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations induced by Catalan automorphisms</a>

%o (Scheme functions implementing this automorphism on list-structures:)

%o (define (gma082351! s) (cond ((not (pair? s)) s) ((not (pair? (car s))) s) ((not (pair? (cdr s))) (robl! (swap! s))) (else (robl! s))))

%o (define (robl! s) (let ((ex-car (car s))) (set-car! s (cddr s)) (set-cdr! (cdr s) ex-car) (swap! (cdr s)) (swap! s) s))

%o (define (swap! s) (let ((ex-car (car s))) (set-car! s (cdr s)) (set-cdr! s ex-car) s))

%Y Inverse of A082352. a(n) = A057163(A082353(A057163(n))). Cf. also A074679-A074680, A082355-A082356, A082361-A082362.

%K nonn

%O 0,3

%A _Antti Karttunen_, Apr 17 2003