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 1-5 of 5 results.

A125976 Signature-permutation of Kreweras' 1970 involution on Dyck paths.

Original entry on oeis.org

0, 1, 3, 2, 8, 6, 5, 7, 4, 22, 19, 15, 20, 14, 13, 11, 18, 21, 16, 10, 12, 17, 9, 64, 60, 52, 61, 51, 41, 39, 55, 62, 53, 38, 40, 54, 37, 36, 33, 29, 34, 28, 50, 47, 59, 63, 56, 43, 48, 57, 42, 27, 25, 32, 35, 30, 46, 49, 58, 44, 24, 26, 31, 45, 23, 196, 191, 178, 192, 177
Offset: 0

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Author

Antti Karttunen, Jan 02 2007

Keywords

Comments

Lalanne shows in the 1992 paper that this automorphism preserves the sum of peak heights, i.e., that A126302(a(n)) = A126302(n) for all n. Furthermore, he also shows that A126306(a(n)) = A057514(n)-1 and likewise, that A057514(a(n)) = A126306(n)+1, for all n >= 1.
Like A069772, this involution keeps symmetric Dyck paths symmetric, but not necessarily same.
The number of cycles and fixed points in range [A014137(n-1)..A014138(n-1)] of this involution seem to be given by A007595 and the "aerated" Catalan numbers [1, 1, 0, 1, 0, 2, 0, 5, 0, 14, 0, 42, ...], thus this is probably a conjugate of A069770 (as well as of A057163).

Crossrefs

Compositions and conjugations with other automorphisms: A125977-A125979, A125980, A126290.

Formula

a(n) = A080300(A125974(A014486(n))).

A126313 Signature-permutation of a Catalan automorphism: composition of A069772 and A125976.

Original entry on oeis.org

0, 1, 3, 2, 8, 5, 6, 4, 7, 22, 13, 15, 12, 14, 19, 21, 16, 11, 18, 10, 20, 17, 9, 64, 36, 41, 35, 40, 52, 53, 38, 34, 39, 55, 51, 37, 54, 60, 63, 32, 62, 31, 56, 59, 47, 33, 50, 27, 58, 49, 26, 43, 44, 29, 61, 30, 24, 57, 48, 25, 46, 42, 28, 23, 45, 196, 106, 120, 105, 119
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Like A069771, A069772, A125976 and A126315/A126316, this automorphism keeps symmetric Dyck paths symmetric, but not necessarily same.

Crossrefs

Inverse: A126314. a(n) = A069772(A125976(n)) = A126290(A069772(n)) = A126315(A057164(n)). The number of cycles, number of fixed points, maximum cycle sizes and LCM's of all cycle sizes in range [A014137(n-1)..A014138(n-1)] of this permutation are given by A127277, A127278, A127279 and A127280. The fixed points are given by A127306. Note the curiosity: this automorphism partitions the A000108(8) = 1430 Catalan structures of size eight (e.g. Dyck paths of length 16) into 79 equivalence classes, of which the largest contains 79 members.

A126314 Signature-permutation of a Catalan automorphism: composition of A125976 and A069772.

Original entry on oeis.org

0, 1, 3, 2, 7, 5, 6, 8, 4, 22, 19, 17, 12, 10, 13, 11, 16, 21, 18, 14, 20, 15, 9, 63, 56, 59, 50, 47, 62, 53, 55, 41, 39, 45, 31, 26, 24, 35, 30, 32, 27, 25, 61, 51, 52, 64, 60, 44, 58, 49, 46, 34, 28, 29, 36, 33, 42, 57, 48, 43, 37, 54, 40, 38, 23, 196, 178, 191, 192, 177
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Like A069771, A069772, A125976 and A126315/A126316, this automorphism keeps symmetric Dyck paths symmetric, but not necessarily same.

Crossrefs

Inverse: A126313. a(n) = A125976(A069772(n)) = A069772(A126290(n)) = A057164(A126316(n)).

A126315 Signature-permutation of a Catalan automorphism: composition of A069771 and A125976.

Original entry on oeis.org

0, 1, 3, 2, 8, 6, 5, 4, 7, 22, 19, 15, 16, 10, 13, 21, 12, 11, 20, 14, 18, 17, 9, 64, 60, 52, 56, 43, 41, 32, 38, 47, 29, 55, 27, 24, 46, 36, 63, 53, 59, 44, 35, 62, 34, 33, 61, 51, 58, 57, 42, 40, 31, 39, 50, 30, 37, 49, 48, 28, 54, 26, 25, 23, 45, 196, 191, 178, 186, 164
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Like A069771, A069772, A125976 and A126313/A126314, this automorphism keeps symmetric Dyck paths symmetric, but not necessarily same.

Crossrefs

Inverse: A126316. a(n) = A069771(A125976(n)) = A126290(A069771(n)) = A126313(A057164(n)). The number of cycles, number of fixed points and maximum cycle sizes in range [A014137(n-1)..A014138(n-1)] of this permutation are given by A127281, A127282 and A127283. See also the comment at A127280.

A126316 Signature-permutation of a Catalan automorphism: composition of A125976 and A069771.

Original entry on oeis.org

0, 1, 3, 2, 7, 6, 5, 8, 4, 22, 13, 17, 16, 14, 19, 11, 12, 21, 20, 10, 18, 15, 9, 63, 35, 62, 61, 34, 59, 32, 55, 52, 29, 45, 44, 42, 37, 56, 30, 53, 51, 28, 50, 27, 41, 64, 36, 31, 58, 57, 54, 47, 25, 39, 60, 33, 26, 49, 48, 40, 24, 46, 43, 38, 23, 196, 120, 106, 148, 78
Offset: 0

Views

Author

Antti Karttunen, Jan 16 2007

Keywords

Comments

Like A069771, A069772, A125976 and A126313/A126314, this automorphism keeps symmetric Dyck paths symmetric, but not necessarily same.

Crossrefs

Inverse: A126315. a(n) = A125976(A069771(n)) = A069771(A126290(n)) = A057164(A126314(n)).
Showing 1-5 of 5 results.