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A057509
Permutation of natural numbers: rotations of the bottom branches of the rooted plane trees encoded by A014486.
19
0, 1, 2, 3, 4, 6, 5, 7, 8, 9, 11, 14, 16, 19, 10, 15, 12, 17, 18, 13, 20, 21, 22, 23, 25, 28, 30, 33, 37, 39, 42, 44, 47, 51, 53, 56, 60, 24, 29, 38, 43, 52, 26, 40, 31, 45, 46, 32, 48, 49, 50, 27, 41, 34, 54, 55, 35, 57, 58, 59, 36, 61, 62, 63, 64, 65, 67, 70, 72, 75, 79, 81
OFFSET
0,3
COMMENTS
The number of objects (rooted planar trees, mountain ranges, parenthesizations) fixed by this permutation can be computed with procedure fixedcount, which gives A034731.
LINKS
A. Karttunen, Gatomorphisms (Includes the complete Scheme program for computing this sequence)
MAPLE
map(CatalanRankGlobal, map(RotateBottomBranchesL, A014486));
RotateBottomBranchesL := n -> pars2binexp(rotateL(binexp2pars(n)));
rotateL := proc(a) if 0 = nops(a) then (a) else [op(cdr(a)), a[1]]; fi; end;
fixedcount := proc(n) local d, z; z := 0; for d in divisors(n) do z := z+C(d-1); od; RETURN(z); end;
PROG
(Scheme function implementing this automorphism on list-structures:) (define (Rol s) (cond ((not (pair? s)) s) (else (append (cdr s) (list (car s))))))
(Destructive variant, see A057501 for RotateHandshakes! and swap!) (define (Rol! s) (cond ((pair? s) (swap! s) (RotateHandshakes! s))) s)
CROSSREFS
Inverse of A057510 and the car/cdr-flipped conjugate of A069775 and also composition of A069770 & A057501, i.e. A057509(n) = A057163(A069775(A057163(n))) = A057501(A069770(n)).
Cycle counts given by A003239. Cf. also A057511.
Sequence in context: A121731 A244322 A129605 * A130919 A127286 A130946
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 03 2000
STATUS
approved