cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-9 of 9 results.

A127289 Signature-permutation of a Catalan automorphism: composition of A127291 and A057164.

Original entry on oeis.org

0, 1, 3, 2, 6, 8, 7, 5, 4, 15, 20, 14, 19, 21, 18, 22, 16, 11, 13, 17, 12, 10, 9, 39, 53, 41, 55, 59, 40, 54, 38, 52, 57, 37, 51, 56, 58, 47, 60, 49, 62, 64, 48, 61, 43, 29, 34, 42, 28, 33, 35, 50, 63, 46, 32, 36, 44, 30, 25, 27, 45, 31, 26, 24, 23, 113, 155, 118, 160, 173
Offset: 0

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Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

This is otherwise like A127291, but uses A127285 instead of A127287 as a "picker permutation" for the function "tau", which can be found in the entry A127291. A014486->parenthesization is given in A014486. This permutation contains some exceptionally large cycles, see A127297.

Crossrefs

Inverse: A127290. a(n) = A127291(A057164(n)) = A057164(A127299(n)). The number of cycles, maximum cycle sizes and LCM's of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of this permutation are given by A127296, A127297 and A127298.

Programs

A127293 Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A127291/A127292.

Original entry on oeis.org

1, 1, 1, 2, 3, 6, 8, 8, 9, 10, 8, 14, 18, 10
Offset: 0

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Author

Antti Karttunen, Jan 16 2007

Keywords

A127294 Maximum cycle size in range [A014137(n-1)..A014138(n-1)] of permutation A127291/A127292.

Original entry on oeis.org

1, 1, 2, 3, 6, 21, 80, 255, 965, 3349, 9366, 30793, 80798, 396492
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

A127295 Least common multiple of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of permutation A127291/A127292.

Original entry on oeis.org

1, 1, 2, 6, 30, 1260, 1680, 19825740, 10028280, 182416547040, 271239404020200, 219240769050559711332360, 6467876945923041743744426827092900, 27867228909478820644943875389480
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

A057501 Signature-permutation of a Catalan Automorphism: Rotate non-crossing chords (handshake) arrangements; rotate the root position of general trees as encoded by A014486.

Original entry on oeis.org

0, 1, 3, 2, 7, 8, 5, 4, 6, 17, 18, 20, 21, 22, 12, 13, 10, 9, 11, 15, 14, 16, 19, 45, 46, 48, 49, 50, 54, 55, 57, 58, 59, 61, 62, 63, 64, 31, 32, 34, 35, 36, 26, 27, 24, 23, 25, 29, 28, 30, 33, 40, 41, 38, 37, 39, 43, 42, 44, 47, 52, 51, 53, 56, 60, 129, 130, 132, 133, 134
Offset: 0

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Author

Antti Karttunen, Sep 03 2000; entry revised Jun 06 2014

Keywords

Comments

This is a permutation of natural numbers induced when "noncrossing handshakes", i.e., Stanley's interpretation (n), "n nonintersecting chords joining 2n points on the circumference of a circle", are rotated.
The same permutation is induced when the root position of plane trees (Stanley's interpretation (e)) is successively changed around the vertices.
For a good illustration how the rotation of the root vertex works, please see the Figure 6, "Rotation of an ordered rooted tree" in Torsten Mütze's paper (on page 24 in 20 May 2014 revision).
For yet another application of this permutation, please see the attached notes for A085197.
By "recursivizing" either the left or right hand side argument of A085201 in the formula, one ends either with A057161 or A057503. By "recursivizing" the both sides, one ends with A057505. - Antti Karttunen, Jun 06 2014

Crossrefs

Inverse: A057502.
Also, a "SPINE"-transform of A074680, and thus occurs as row 17 of A122203. (Also as row 65167 of A130403.)
Successive powers of this permutation, a^2(n) - a^6(n): A082315, A082317, A082319, A082321, A082323.
Cf. also A057548, A072771, A072772, A085201, A002995 (cycle counts), A057543 (max cycle lengths), A085197, A129599, A057517, A064638, A064640.

Programs

  • Maple
    map(CatalanRankGlobal,map(RotateHandshakes, A014486));
    RotateHandshakes := n -> pars2binexp(RotateHandshakesP(binexp2pars(n)));
    RotateHandshakesP := h -> `if`((0 = nops(h)),h,[op(car(h)),cdr(h)]); # This does the trick! In Lisp: (defun RotateHandshakesP (h) (append (car h) (list (cdr h))))
    car := proc(a) if 0 = nops(a) then ([]) else (op(1,a)): fi: end: # The name is from Lisp, takes the first element (head) of the list.
    cdr := proc(a) if 0 = nops(a) then ([]) else (a[2..nops(a)]): fi: end: # As well. Takes the rest (the tail) of the list.
    PeelNextBalSubSeq := proc(nn) local n,z,c; if(0 = nn) then RETURN(0); fi; n := nn; c := 0; z := 0; while(1 = 1) do z := 2*z + (n mod 2); c := c + (-1)^n; n := floor(n/2); if(c >= 0) then RETURN((z - 2^(floor_log_2(z)))/2); fi; od; end;
    RestBalSubSeq := proc(nn) local n,z,c; n := nn; c := 0; while(1 = 1) do c := c + (-1)^n; n := floor(n/2); if(c >= 0) then break; fi; od; z := 0; c := -1; while(1 = 1) do z := 2*z + (n mod 2); c := c + (-1)^n; n := floor(n/2); if(c >= 0) then RETURN(z/2); fi; od; end;
    pars2binexp := proc(p) local e,s,w,x; if(0 = nops(p)) then RETURN(0); fi; e := 0; for s in p do x := pars2binexp(s); w := floor_log_2(x); e := e * 2^(w+3) + 2^(w+2) + 2*x; od; RETURN(e); end;
    binexp2pars := proc(n) option remember; `if`((0 = n),[],binexp2parsR(binrev(n))); end;
    binexp2parsR := n -> [binexp2pars(PeelNextBalSubSeq(n)),op(binexp2pars(RestBalSubSeq(n)))];
    # Procedure CatalanRankGlobal given in A057117, other missing ones in A038776.

Formula

a(0) = 0, and for n>=1, a(n) = A085201(A072771(n), A057548(A072772(n))). [This formula reflects directly the given non-destructive Lisp/Scheme function: A085201 is a 2-ary function corresponding to 'append', A072771 and A072772 correspond to 'car' and 'cdr' (known also as first/rest or head/tail in some dialects), and A057548 corresponds to unary form of function 'list'].
As a composition of related permutations:
a(n) = A057509(A069770(n)).
a(n) = A057163(A069773(A057163(n))).
Invariance-identities:
A129599(a(n)) = A129599(n) holds for all n.

A127287 Signature-permutation of a Catalan automorphism: composition of A127285 and A057508.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 28, 24, 30, 33, 25, 29, 26, 31, 32, 27, 34, 35, 36, 37, 39, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 79, 67, 84, 93, 66, 80
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

This automorphism permutes the top-level of a list of even length (1 ... 2n) as (1 2n 2 2n-1 3 2n-3 ... n n+1) and when applied to a list of odd length (1 .. 2n+1), permutes it as (1 2n+1 2 2n 3 2n-1 ... n n+1). Used to construct A127291.

Crossrefs

Inverse: A127288. a(n) = A127285(A057508(n)).

A127292 Signature-permutation of the inverse of Elizalde's and Deutsch's 2003 bijection for Dyck paths.

Original entry on oeis.org

0, 1, 3, 2, 8, 7, 4, 5, 6, 22, 21, 17, 18, 20, 11, 9, 12, 13, 10, 16, 14, 19, 15, 64, 63, 58, 59, 62, 48, 45, 49, 50, 46, 57, 54, 61, 55, 33, 30, 23, 25, 28, 34, 31, 35, 36, 32, 24, 26, 29, 27, 47, 44, 37, 39, 42, 56, 53, 60, 51, 38, 40, 43, 41, 52, 196, 195, 189, 190, 194
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Note that this automorphism cannot be produced just by giving A127288 (the inverse of A127287) to function "tau" given in A127291. Instead, we have to use another algorithm given in A127300 and then conjugate it by A057164.

References

  • Emeric Deutsch and Sergi Elizalde, A simple and unusual bijection for Dyck paths and its consequences, Annals of Combinatorics, 7 (2003), no. 3, 281-297.

Crossrefs

Inverse: A127291. a(n) = A057164(A127290(n)) = A057164(A127300(A057164(n))).

A127300 Signature-permutation of A057164-conjugate of the inverse of Elizalde's and Deutsch's 2003 bijection for Dyck paths.

Original entry on oeis.org

0, 1, 3, 2, 8, 4, 7, 6, 5, 22, 11, 17, 16, 12, 21, 9, 20, 19, 10, 18, 14, 13, 15, 64, 33, 48, 47, 34, 58, 23, 57, 56, 24, 49, 37, 35, 38, 63, 30, 45, 44, 31, 62, 28, 61, 60, 29, 46, 42, 32, 43, 59, 25, 54, 53, 26, 50, 39, 36, 40, 55, 51, 27, 52, 41, 196, 102, 145, 144, 103
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Used to construct the inverse for A127291.

References

  • Emeric Deutsch and Sergi Elizalde, A simple and unusual bijection for Dyck paths and its consequences, Annals of Combinatorics, 7 (2003), no. 3, 281-297.

Crossrefs

Inverse: A127299. a(n) = A057164(A127292(A057164(n))) = A127290(A057164(n)). Cf. A014486.

A127299 Signature-permutation of A057164-conjugate of Elizalde's and Deutsch's 2003 bijection for Dyck paths.

Original entry on oeis.org

0, 1, 3, 2, 5, 8, 7, 6, 4, 15, 18, 10, 13, 21, 20, 22, 12, 11, 19, 17, 16, 14, 9, 29, 32, 52, 55, 62, 43, 46, 38, 41, 49, 24, 27, 35, 58, 34, 36, 57, 59, 64, 48, 50, 40, 39, 47, 26, 25, 33, 56, 61, 63, 54, 53, 60, 31, 30, 28, 51, 45, 44, 42, 37, 23, 113, 116, 136, 139, 146
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

References

  • Emeric Deutsch and Sergi Elizalde, A simple and unusual bijection for Dyck paths and its consequences, Annals of Combinatorics, 7 (2003), no. 3, 281-297.

Crossrefs

Inverse: A127300. a(n) = A057164(A127291(A057164(n))) = A057164(A127289(n)).

Programs

Showing 1-9 of 9 results.