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%I #7 Mar 31 2012 13:21:12
%S 0,1,2,3,4,6,7,5,8,9,10,14,16,19,17,18,12,11,13,20,15,21,22,23,24,25,
%T 26,27,37,38,42,44,47,51,53,56,60,45,46,48,49,50,31,32,30,28,29,34,33,
%U 35,36,54,55,40,39,41,57,43,58,59,61,52,62,63,64,65,66,67,68,69,70,71
%N Signature permutation of a nonrecursive Catalan automorphism: row 1655089 of table A089840.
%H A. Karttunen, <a href="/A089840/a089840p.txt">Prolog-program which illustrates the construction of this and other similar nonrecursive Catalan automorphisms.</a>
%H <a href="/index/Per#IntegerPermutationCatAuto">Index entries for signature-permutations of Catalan automorphisms</a>
%o (Scheme function, destructive implementation of this automorphism acting on S-expressions:) (define (*A123497! s) (cond ((null? s) s) ((and (pair? (car s)) (pair? (cdar s))) (*A074680! s) (let ((old-cddr-s (cddr s))) (set-cdr! (cdr s) (cdadr s)) (set-cdr! (cadr s) old-cddr-s))) ((pair? (car s)) (*A072797! s)) ((pair? (cdr s)) (*A072796! s))) s)
%Y Inverse: A123498. Row 1655089 of A089840. Used to construct automorphism *A123501. A074680(n) = A083927(a(A057123(n))).
%K nonn
%O 0,3
%A _Antti Karttunen_, Oct 11 2006
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