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 A072636 Permutation of natural numbers induced by reranking plane binary trees given in the standard lexicographic order (A014486) with an "arithmetic global ranking algorithm", using packA054238tr as the packing bijection N X N -> N. 6
 0, 1, 2, 3, 5, 6, 4, 9, 11, 18, 21, 17, 66, 70, 7, 8, 10, 35, 41, 12, 33, 131, 139, 261, 274, 258, 4101, 4117, 22, 65, 69, 1030, 1090, 81, 1026, 16390, 16454, 20, 23, 19, 68, 72, 13, 14, 36, 521, 547, 42, 515, 8201, 8233, 15, 16, 34, 43, 129, 132, 137, 2059, 2179 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS A. Karttunen, Gatomorphisms PROG (Scheme functions below show the essential idea. For a complete source, follow the "Gatomorphisms" link.) (define A072636 (lexrank->arithrank-bijection packA054238tr)) (define (lexrank->arithrank-bijection packfun) (lambda (n) (rank-bintree (binexp->parenthesization (A014486 n)) packfun))) (define (rank-bintree bt packfun) (cond ((not (pair? bt)) 0) (else (1+ (packfun (rank-bintree (car bt) packfun) (rank-bintree (cdr bt) packfun)))))) (define (packA054238tr x y) (+ (A000695 y) (* 2 (A000695 x)))) CROSSREFS Inverse permutation: A072637. Cf. also A014486, A000695, A054238, A071651, A072634, A072646, A072656, A072658, A072644. Sequence in context: A194051 A195610 A082654 * A191741 A191665 A254105 Adjacent sequences:  A072633 A072634 A072635 * A072637 A072638 A072639 KEYWORD nonn AUTHOR Antti Karttunen, Jun 02 2002 STATUS approved

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Last modified January 17 10:59 EST 2019. Contains 319218 sequences. (Running on oeis4.)