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A072768
The RASTxx transformation of the sequence A072643.
6
1, 2, 2, 3, 3, 3, 3, 4, 4, 3, 4, 4, 5, 4, 4, 4, 5, 5, 5, 5, 4, 4, 5, 6, 5, 6, 5, 4, 4, 5, 6, 6, 6, 6, 5, 4, 4, 5, 6, 6, 7, 6, 6, 5, 4, 5, 5, 6, 6, 7, 7, 6, 6, 5, 5, 5, 6, 6, 6, 7, 7, 7, 6, 6, 6, 5, 5, 6, 7, 6, 7, 7, 7, 7, 6, 7, 6, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 6, 5, 5, 6, 7, 7, 8, 7, 7, 7, 7, 8, 7, 7, 6, 5
OFFSET
1,2
COMMENTS
Also, the sizes of the parenthesizations produced by 'cons' combination A072764 and its transpose A072766.
Differs from A071673 first time at the position n=37, where A072768(37) = 4, while A071673(37) = 5. RASTxx(A072768) differs from A071673 first time at the position n=704, which leads to conjecture that the repeated applications of RASTxx starting from A072643 converge towards A071673, the fixed point of RASTxx transformation.
Each value v occurs A000108(v) times. (The term a(0)=0 is not explicitly listed here as to get a better looking triangle).
LINKS
A. Karttunen, Gatomorphisms (Includes the complete Scheme source for computing this sequence)
N. J. A. Sloane, Transforms (Maple code for RASTxx transform)
PROG
(Scheme) (define (A072768 n) (cond ((zero? n) n) (else (+ 1 (A072643 (A025581 (-1+ n))) (A072643 (A002262 (-1+ n)))))))
CROSSREFS
Same triangle computed modulo 2: A072770. Permutations: A072643, A071673, A072644, A072645, A072660, A072789. Cf. also A072769, A025581, A002262.
Sequence in context: A115777 A340033 A316847 * A071673 A174199 A072660
KEYWORD
nonn,tabl,changed
AUTHOR
Antti Karttunen, Jun 12 2002
STATUS
approved