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A072656
Permutation of natural numbers induced by reranking plane binary trees given in the standard lexicographic order (A014486) with an "arithmetic global ranking algorithm", using packA048680oA054238 as the packing bijection N X N -> N.
8
0, 1, 3, 2, 11, 6, 5, 7, 4, 100, 27, 24, 45, 14, 18, 10, 13, 62, 17, 8, 15, 28, 9, 1988, 477, 179, 1100, 116, 150, 61, 113, 2090, 147, 35, 189, 302, 58, 162, 44, 39, 73, 23, 34, 20, 102, 1229, 295, 29, 111, 680, 72, 21, 12, 26, 93, 38, 47, 70, 1292, 91, 16, 22, 117, 187
OFFSET
0,3
PROG
(Scheme functions below show the essential idea. For a complete source, follow the "Gatomorphisms" link.)
(define A072656 (lexrank->arithrank-bijection packA048680oA054238))
(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 (packA048680oA054238 x y) (A048680 (packA054238 x y)))
(define (packA054238 x y) (+ (A000695 x) (* 2 (A000695 y))))
CROSSREFS
Sequence in context: A238398 A065014 A013945 * A330313 A191669 A344891
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 02 2002
STATUS
approved