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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.

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A122201 Signature permutations of FORK-transformations of non-recursive Catalan automorphisms in table A089840.

Original entry on oeis.org

0, 1, 0, 2, 1, 0, 3, 3, 1, 0, 4, 2, 2, 1, 0, 5, 8, 3, 2, 1, 0, 6, 7, 4, 3, 2, 1, 0, 7, 6, 6, 5, 3, 2, 1, 0, 8, 5, 5, 4, 5, 3, 2, 1, 0, 9, 4, 7, 6, 6, 6, 3, 2, 1, 0, 10, 22, 8, 7, 4, 5, 6, 3, 2, 1, 0, 11, 21, 9, 8, 7, 4, 4, 4, 3, 2, 1, 0, 12, 20, 11, 12, 8, 7, 5, 5, 4, 3, 2, 1, 0, 13, 18, 14, 13, 12
Offset: 0

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Author

Antti Karttunen, Sep 01 2006

Keywords

Comments

Row n is the signature permutation of the Catalan automorphism which is obtained from the n-th nonrecursive automorphism in the table A089840 with the recursion scheme "FORK". In this recursion scheme the given automorphism is first applied at the root of binary tree, before the algorithm recurses down to the both branches (new ones, possibly changed by the given automorphism). I.e. this corresponds to the pre-order (prefix) traversal of a Catalan structure, when it is interpreted as a binary tree. The associated Scheme-procedures FORK and !FORK can be used to obtain such a transformed automorphism from any constructively or destructively implemented automorphism. Each row occurs only once in this table. Inverses of these permutations can be found in table A122202.

References

  • A. Karttunen, paper in preparation, draft available by e-mail.

Links

Crossrefs

The first 22 rows of this table: row 0 (identity permutation): A001477, 1: A057163, 2: A057511, 3: A122341, 4: A122343, 5: A122345, 6: A122347, 7: A122349, 8: A082325, 9: A082360, 10: A122291, 11: A122293, 12: A074681, 13: A122295, 14: A122297, 15: A122353, 16: A122355, 17: A074684, 18: A122357, 19: A122359, 20: A122361, 21: A122301. Other rows: row 4253: A082356, row 65796: A082358, row 79361: A123493.
See also tables A089840, A122200, A122202-A122204, A122283-A122284, A122285-A122288, A122289-A122290.

Programs

  • Scheme
    (define (FORK foo) (letrec ((bar (lambda (s) (let ((t (foo s))) (if (pair? t) (cons (bar (car t)) (bar (cdr t))) t))))) bar))
(define (!FORK foo!) (letrec ((bar! (lambda (s) (cond ((pair? s) (foo! s) (bar! (car s)) (bar! (cdr s)))) s))) bar!))

A122298 Row 19 of A122202.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Sep 01 2006

Keywords

Comments

The signature-permutation of the automorphism which is derived from the nineteenth non-recursive automorphism *A073270 with recursion schema KROF (see A122202 for the definition).

Links

Crossrefs

Inverse: A122297.
Showing 1-2 of 2 results.

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