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A071653
Permutation of natural numbers induced by reranking plane binary trees given in the standard lexicographic order (A014486) with an "arithmetic global ranking algorithm", using the bivariate form of A001477 as the packing bijection N x N -> N.
4
0, 1, 3, 2, 10, 6, 5, 7, 4, 66, 28, 21, 36, 15, 14, 9, 12, 56, 22, 8, 16, 29, 11, 2278, 435, 253, 703, 136, 120, 55, 91, 1653, 276, 45, 153, 465, 78, 77, 35, 27, 44, 20, 25, 18, 68, 2212, 407, 30, 232, 667, 121, 19, 13, 23, 106, 46, 38, 79, 1597, 254, 17, 37, 137, 436
OFFSET
0,3
COMMENTS
A071653(A014137(n-1)) = A072638(n) for all n > 0. - Paul D. Hanna, Jan 04 2007
Also seems that A071653(A014137(n)-1) = A006894(n) for all n > 0. - Antti Karttunen, Jul 30 2012
PROG
(Scheme functions below show the essential idea. For a complete source, see the "Alternative Catalan Orderings" OEIS Wiki page.)
(define lexrank->arithrankA001477 (lexrank->arithrank-bijection packA001477))
(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 (packA001477 x y) (/ (+ (expt (+ x y) 2) x (* 3 y)) 2))
CROSSREFS
Inverse permutation: A071654. Cf. also A014486, A001477, A071651, A071652.
Sequence in context: A318280 A057977 A063549 * A227631 A246830 A268531
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 30 2002
STATUS
approved