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A075161 Position of A075165(n+1) in A014486. 6
0, 1, 2, 3, 4, 5, 9, 7, 6, 10, 23, 12, 65, 24, 11, 8, 197, 15, 626, 26, 25, 66, 2056, 13, 14, 198, 16, 68, 6918, 29, 23714, 17, 67, 627, 28, 40, 82500, 2057, 199, 27, 290512, 71, 1033412, 200, 30, 6919, 3707852, 31, 37, 38, 628, 629, 13402697, 43, 70, 69, 2058 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
See A075166.
LINKS
A. Karttunen, Alternative Catalan Orderings (with the complete Scheme source)
PROG
(Scheme functions showing the essential idea. For the complete source, follow the "Alternative Catalan Orderings" link:)
(define (A075161 n) (CatalanRankGlobal (parenthesization->binexp (primefactorization->parenthesization (1+ n)))))
(define (primefactorization->parenthesization n) (map primefactorization->parenthesization (explist->Nvector! (primefactorization->explist n))))
Function primefactorization->explist maps 1 to (), 2 to (1), 3 to (1 0), 4 to (2), 12 to (1 2), etc.
(define (explist->Nvector! el) (cond ((pair? el) (let loop ((el (cdr el))) (cond ((pair? el) (set-car! el (1+ (car el))) (loop (cdr el))))))) el)
CROSSREFS
Inverse of A075162. a(n) = A075163(n+1)-1. Cf. A075168.
Sequence in context: A346097 A346098 A245821 * A298268 A329044 A222251
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 13 2002
STATUS
approved

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)