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.

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A154442 Permutation of nonnegative integers: the inverse of A154441.

Original entry on oeis.org

0, 1, 3, 2, 6, 7, 4, 5, 12, 13, 15, 14, 8, 9, 10, 11, 24, 25, 26, 27, 30, 31, 28, 29, 16, 17, 18, 19, 20, 21, 22, 23, 48, 49, 50, 51, 52, 53, 54, 55, 60, 61, 63, 62, 56, 57, 58, 59, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 96, 97, 98, 99, 100, 101, 102
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Crossrefs

Inverse: A154441. a(n) = A153141(A154444(n)) = A054429(A154446(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154439-A154448. Corresponds to A154452 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154446 Permutation of nonnegative integers: The inverse of A154445.

Original entry on oeis.org

0, 1, 3, 2, 6, 7, 4, 5, 12, 13, 14, 15, 9, 8, 10, 11, 24, 25, 26, 27, 28, 29, 30, 31, 18, 19, 16, 17, 20, 21, 22, 23, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 36, 37, 38, 39, 33, 32, 34, 35, 40, 41, 42, 43, 44, 45, 46, 47, 96, 97, 98, 99, 100, 101, 102
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Crossrefs

Inverse: A154445. a(n) = A153142(A154440(n)) = A054429(A154442(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154439-A154448. Corresponds to A154456 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154449 Signature permutation of a Catalan bijection induced by generator "a" of the rightward recursing instance of Basilica group wreath recursion: a = (1,b), b = s(1,a).

Original entry on oeis.org

0, 1, 2, 3, 5, 4, 6, 7, 8, 12, 13, 11, 9, 10, 15, 14, 16, 17, 18, 19, 20, 21, 22, 32, 31, 34, 35, 36, 30, 33, 28, 23, 24, 29, 25, 26, 27, 40, 41, 39, 37, 38, 43, 42, 44, 45, 46, 47, 48, 49, 50, 52, 51, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 91, 92, 90, 87, 88, 97, 96
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Comments

This automorphism of rooted plane binary trees switches the two descendant trees for every other vertex as it returns back toward the root, after descending down to the rightmost tip of the tree along the 111... ray, so that the last vertex whose descendants are swapped, is the right-hand side child of the root and the root itself is fixed. Specifically, *A154449 = psi(A154439), where the isomorphism psi is given in A153141 (see further comments there).

Crossrefs

Inverse: A154450. a(n) = A154455(A069768(n)) = A057163(A154453(A057163(n))). Cf. A154451.

A071163 A014486-indices for rooted binary trees with height equal to number of internal vertices. (Binary trees where at each internal vertex at least the other child is leaf.)

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 7, 8, 9, 10, 12, 13, 17, 18, 21, 22, 23, 24, 26, 27, 31, 32, 35, 36, 45, 46, 49, 50, 58, 59, 63, 64, 65, 66, 68, 69, 73, 74, 77, 78, 87, 88, 91, 92, 100, 101, 105, 106, 129, 130, 133, 134, 142, 143, 147, 148, 170, 171, 175, 176, 189, 190, 195, 196, 197
Offset: 0

Views

Author

Antti Karttunen, May 14 2002

Keywords

Comments

This subset of integers is closed by the actions of A069770, A057163, A069767, A069768, A122353, A122354, A122301, A122302, etc. (meaning, e.g., that A069767(a(n)) is a member from this sequence for all n), that is, by any Catalan bijection which is an image of some element of the automorphism group of infinite binary tree (the latter in a sense given by Grigorchuk, et al., being isomorphic to an infinitely iterated wreath product of cyclic groups of two elements). See the comments about the isomorphism "psi" given at A153141.
a(n) could be probably computed directly from the binary expansion of n by using a (somewhat) similar ranking function as given in A209640, but utilizing A009766 instead of A007318.

Formula

a(n) = A080300(A071162(n)).

A154440 Permutation of nonnegative integers: the inverse of A154439.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 7, 6, 8, 9, 10, 11, 14, 15, 12, 13, 16, 17, 18, 19, 20, 21, 22, 23, 28, 29, 31, 30, 24, 25, 26, 27, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 56, 57, 58, 59, 62, 63, 60, 61, 48, 49, 50, 51, 52, 53, 54, 55, 64, 65, 66, 67, 68, 69, 70, 71
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Crossrefs

Inverse: A154439. a(n) = A153141(A154446(n)) = A054429(A154444(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154442-A154448. Corresponds to A154450 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154441 Permutation of nonnegative integers induced by Basilica group generating wreath recursion: a = (1,b), b = s(1,a), starting from the active (swapping) state b.

Original entry on oeis.org

0, 1, 3, 2, 6, 7, 4, 5, 12, 13, 14, 15, 8, 9, 11, 10, 24, 25, 26, 27, 28, 29, 30, 31, 16, 17, 18, 19, 22, 23, 20, 21, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 32, 33, 34, 35, 36, 37, 38, 39, 44, 45, 46, 47, 40, 41, 43, 42, 96, 97, 98, 99, 100, 101, 102
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Comments

This permutation is induced by the Basilica group generating wreath recursion a = (1,b), b = s(1,a) (i.e. binary transducer, where s means that the bits at that state are toggled: 0 <-> 1) given on the page 40 of Bartholdi and Virag paper, starting from the active (switching) state b and rewriting bits from the second most significant bit to the least significant end.

Examples

			Starting from the second most significant bit, we continue complementing every second bit (in this case, starting from the second most significant bit), as long as the first zero is encountered, which is also complemented if its distance to the most significant bit is odd, after which the remaining bits are left intact. E.g. 121 = 1111001 in binary. Complementing its second and fourth most significant bits (positions 5 & 3) and stopping at the first zero-bit at position 2 (which is not complemented, as its distance to the msb is 6), we obtain "10100.." after which the rest of the bits stay same, so we get 1010001, which is 81's binary representation, thus a(121)=81. On the other hand, 125 = 1111101 in binary and the transducer complements the bits at positions 5, 3 and also the first zero at the position 1 (because at odd distance from the msb), yielding 101011., after which the remaining bit stays same, thus we get 1010111, which is 87's binary representation, thus a(125)=87.
		

References

  • R. I. Grigorchuk and A. Zuk, Spectral properties of a torsion free weakly branch group defined by a three state automaton, Contemporary Mathematics 298 (2002), 57--82.

Crossrefs

Inverse: A154442. a(n) = A154443(A153142(n)) = A054429(A154445(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154439-A154448. Corresponds to A154451 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154443 Permutation of nonnegative integers induced by Basilica group generating wreath recursion: a = (b,1), b = s(a,1), starting from the inactive (fixing) state a.

Original entry on oeis.org

0, 1, 2, 3, 5, 4, 6, 7, 10, 11, 8, 9, 12, 13, 14, 15, 21, 20, 22, 23, 16, 17, 18, 19, 24, 25, 26, 27, 28, 29, 30, 31, 42, 43, 40, 41, 44, 45, 46, 47, 32, 33, 34, 35, 36, 37, 38, 39, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 85, 84, 86, 87, 80, 81, 82, 83
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Crossrefs

Inverse: A154444. a(n) = A154441(A153141(n)) = A054429(A154439(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154439-A154448. Corresponds to A154453 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154445 Permutation of nonnegative integers induced by Basilica group generating wreath recursion: a = (b,1), b = s(a,1), starting from the active (swapping) state b.

Original entry on oeis.org

0, 1, 3, 2, 6, 7, 4, 5, 13, 12, 14, 15, 8, 9, 10, 11, 26, 27, 24, 25, 28, 29, 30, 31, 16, 17, 18, 19, 20, 21, 22, 23, 53, 52, 54, 55, 48, 49, 50, 51, 56, 57, 58, 59, 60, 61, 62, 63, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 106, 107, 104, 105, 108, 109
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Crossrefs

Inverse: A154446. a(n) = A154439(A153141(n)) = A054429(A154441(A054429(n))). Cf. A072376, A153141-A153142, A154435-A154436, A154439-A154448. Corresponds to A154455 in the group of Catalan bijections.

Extensions

Spelling/notation corrections by Charles R Greathouse IV, Mar 18 2010

A154450 Signature permutation of a Catalan bijection: The inverse of A154449.

Original entry on oeis.org

0, 1, 2, 3, 5, 4, 6, 7, 8, 12, 13, 11, 9, 10, 15, 14, 16, 17, 18, 19, 20, 21, 22, 31, 32, 34, 35, 36, 30, 33, 28, 24, 23, 29, 25, 26, 27, 40, 41, 39, 37, 38, 43, 42, 44, 45, 46, 47, 48, 49, 50, 52, 51, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 87, 88, 90, 91, 92, 96, 97
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Comments

This automorphism of rooted plane binary trees switches the two descendant trees for every other vertex as it descends along the 111... ray, but not starting swapping until at the right-hand side child of the root, leaving the root itself fixed. Specifically, *A154450 = psi(A154440), where the isomorphism psi is given in A153141 (see further comments there).

Crossrefs

Inverse: A154449. a(n) = A069767(A154456(n)) = A057163(A154454(A057163(n))). Cf. A069770, A154452.
Differs from A089850 for the first time at n=31, where a(31)=24, while A089850(31)=23.

A154451 Signature permutation of a Catalan bijection induced by generator "b" of the rightward recursing instance of Basilica group wreath recursion: a = (1,b), b = s(1,a).

Original entry on oeis.org

0, 1, 3, 2, 7, 8, 6, 4, 5, 18, 17, 20, 21, 22, 16, 19, 14, 9, 10, 15, 11, 12, 13, 49, 50, 48, 45, 46, 55, 54, 57, 58, 59, 61, 62, 63, 64, 47, 44, 53, 56, 60, 42, 51, 37, 23, 24, 38, 25, 26, 27, 43, 52, 39, 28, 29, 40, 30, 31, 32, 41, 33, 34, 35, 36, 143, 142, 146, 147, 148
Offset: 0

Views

Author

Antti Karttunen, Jan 17 2009

Keywords

Comments

This automorphism of rooted plane binary trees switches the two descendant trees for every other vertex as it returns back toward the root, after descending down to the rightmost tip of the tree along the 111... ray, so that the last vertex whose descendants are swapped is the root node of the tree. Specifically, *A154451 = psi(A154441), where the isomorphism psi is given in A153141 (see further comments there).

Crossrefs

Inverse: A154452. a(n) = A154453(A069768(n)) = A057163(A154455(A057163(n))). Cf. A069770, A154449.
Previous Showing 11-20 of 34 results. Next