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.

Previous Showing 41-49 of 49 results.

A054069 Inverse of the permutation A054068 of natural numbers.

Original entry on oeis.org

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

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Author

Keywords

Comments

As an interspersion, row n gives the positions of n in the fractal sequence A054065.

Examples

			Northwest corner, as an interspersion:
1...2...5...8...12..18..24
3...6...10..14..20..27..35
4...7...11..16..22..30..38
9...13..19..25..33..42..51
15..21..28..36..45..55..66
		

Crossrefs

Programs

A194837 Inverse permutation of A194836; every positive integer occurs exactly once.

Original entry on oeis.org

1, 3, 2, 5, 4, 6, 8, 10, 7, 9, 12, 14, 11, 13, 15, 17, 19, 21, 16, 18, 20, 28, 23, 25, 27, 22, 24, 26, 35, 30, 32, 34, 29, 36, 31, 33, 43, 38, 45, 40, 42, 37, 44, 39, 41, 52, 47, 54, 49, 51, 46, 53, 48, 55, 50, 62, 57, 64, 59, 66, 61, 56, 63, 58, 65, 60, 78, 73, 68
Offset: 1

Views

Author

Clark Kimberling, Sep 03 2011

Keywords

Crossrefs

Programs

A194840 Inverse permutation of A194839; every positive integer occurs exactly once.

Original entry on oeis.org

1, 3, 2, 6, 5, 4, 9, 8, 7, 10, 13, 12, 15, 11, 14, 18, 21, 17, 20, 16, 19, 28, 24, 27, 23, 26, 22, 25, 35, 31, 34, 30, 33, 29, 36, 32, 43, 39, 42, 38, 45, 41, 37, 44, 40, 52, 48, 55, 51, 47, 54, 50, 46, 53, 49, 66, 62, 58, 65, 61, 57, 64, 60, 56, 63, 59, 77, 73, 69
Offset: 1

Views

Author

Clark Kimberling, Sep 03 2011

Keywords

Crossrefs

Programs

A194864 Inverse permutation of A194866; every positive integer occurs exactly once.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 10, 7, 8, 9, 14, 11, 15, 12, 13, 19, 16, 20, 17, 21, 18, 25, 22, 26, 23, 27, 24, 28, 32, 36, 29, 33, 30, 34, 31, 35, 40, 44, 37, 41, 45, 38, 42, 39, 43, 49, 53, 46, 50, 54, 47, 51, 55, 48, 52, 66, 59, 63, 56, 60, 64, 57, 61, 65, 58, 62, 77, 70, 74
Offset: 1

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Author

Clark Kimberling, Sep 04 2011

Keywords

Crossrefs

Programs

Extensions

Definition corrected by Georg Fischer, Jul 30 2023

A194867 Inverse permutation of A194863; every positive integer occurs exactly once.

Original entry on oeis.org

1, 2, 3, 6, 4, 5, 9, 7, 10, 8, 13, 11, 14, 12, 15, 18, 21, 16, 19, 17, 20, 24, 27, 22, 25, 28, 23, 26, 31, 34, 29, 32, 35, 30, 33, 36, 39, 42, 45, 37, 40, 43, 38, 41, 44, 48, 51, 54, 46, 49, 52, 55, 47, 50, 53, 66, 58, 61, 64, 56, 59, 62, 65, 57, 60, 63, 77, 69, 72
Offset: 1

Views

Author

Clark Kimberling, Sep 04 2011

Keywords

Crossrefs

Programs

Extensions

Definition corrected by Georg Fischer, Jul 30 2023

A194834 Inverse permutation of A194833; every positive integer occurs exactly once.

Original entry on oeis.org

1, 2, 3, 6, 4, 5, 9, 7, 10, 8, 13, 11, 14, 12, 15, 18, 21, 16, 19, 17, 20, 24, 27, 22, 25, 28, 23, 26, 36, 31, 34, 29, 32, 35, 30, 33, 44, 39, 42, 37, 45, 40, 43, 38, 41, 53, 48, 51, 46, 54, 49, 52, 47, 55, 50, 63, 58, 66, 61, 56, 64, 59, 62, 57, 65, 60, 74, 69, 77
Offset: 1

Views

Author

Clark Kimberling, Sep 03 2011

Keywords

Crossrefs

Programs

A215345 Value of y in the n-th number of the form x+y*(1+sqrt(5))/2.

Original entry on oeis.org

0, 0, 1, 0, 1, 0, 2, 1, 0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 4, 1, 3, 0, 2, 4, 1, 3, 0, 5, 2, 4, 1, 3, 0, 5, 2, 4, 1, 6, 3, 0, 5, 2, 4, 1, 6, 3, 0, 5, 2, 7, 4, 1, 6, 3, 0, 5, 2, 7, 4, 1, 6, 3, 8, 0, 5, 2, 7, 4, 1, 6, 3, 8, 0, 5, 2, 7, 4, 9, 1, 6, 3, 8, 0, 5, 2, 7, 4, 9, 1, 6, 3, 8, 0, 5, 10, 2, 7, 4, 9, 1, 6, 3, 8, 0, 5, 10, 2, 7, 4, 9, 1, 6, 11, 3, 8
Offset: 1

Views

Author

Peter G. Anderson, Aug 08 2012

Keywords

Comments

Let x>=0, y>=0 be integers, sort according to x+y*(1+sqrt(5))/2, this sequence gives the y-values. - Joerg Arndt, Aug 16 2012

Examples

			Let g = (1+sqrt(5))/2, sequences A215344 (x) and A215345 (y) start as:
[x+y*g, x, y]
[0.0000000, 0, 0]
[1.0000000, 1, 0]
[1.6180340, 0, 1]
[2.0000000, 2, 0]
[2.6180340, 1, 1]
[3.0000000, 3, 0]
[3.2360680, 0, 2]
[3.6180340, 2, 1]
[4.0000000, 4, 0]
[4.2360680, 1, 2]
[4.6180340, 3, 1]
[4.8541020, 0, 3]
[5.0000000, 5, 0]
[5.2360680, 2, 2]
[5.6180340, 4, 1]
- _Joerg Arndt_, Aug 17 2012.
		

Crossrefs

A215344 is the value of x.

Programs

A372231 Fixed points of A372341.

Original entry on oeis.org

1, 2, 5, 8, 12, 18, 24, 32, 40, 49, 60, 71, 83, 97, 111, 127, 143, 160, 179, 198, 219, 240, 262, 286, 310, 335, 362, 389, 418, 447, 477, 509, 541, 574, 609, 644, 681, 718, 756, 796, 836, 878, 920, 963, 1008, 1053, 1099, 1147, 1195, 1245, 1295, 1346, 1399, 1452
Offset: 1

Views

Author

Rémy Sigrist, Apr 28 2024

Keywords

Examples

			A372341(49) = 49, so 49 belongs to this sequence.
		

Crossrefs

Formula

a(n) = A000217(n) - A005206(n-1).
A194832(a(n)) = 1. Also the first row A194833(1, n) = a(n). This can be seen in the EXAMPLE section of A372341. Each row is horizontally shifted by a value from A005206. The shift is known to be floor((k+1)*tau)-k-1, where tau is the golden ratio. The position of "1" in a permutation from A194832 is determined by a similar process based on the same constant. - Thomas Scheuerle, Jul 08 2024

A371822 Triangle read by rows. Row n is the lexicographically earliest permutation of [n] that can be obtained from row n-1 by inserting the element n and optional cyclic shifting to maximize the pattern density.

Original entry on oeis.org

1, 1, 2, 3, 1, 2, 3, 1, 4, 2, 2, 5, 3, 1, 4, 2, 5, 3, 6, 1, 4, 3, 6, 1, 4, 7, 2, 5, 2, 5, 8, 3, 6, 1, 4, 7, 6, 1, 9, 4, 7, 2, 5, 8, 3, 7, 2, 10, 5, 8, 3, 6, 1, 9, 4, 7, 2, 10, 5, 8, 3, 11, 6, 1, 9, 4, 8, 3, 11, 6, 1, 9, 4, 12, 7, 2, 10, 5, 11, 6, 1, 9, 4, 12, 7, 2, 10, 5, 13, 8, 3, 11, 6, 1, 14, 9, 4, 12, 7, 2, 10, 5, 13, 8, 3
Offset: 1

Views

Author

Thomas Scheuerle, Jun 22 2024

Keywords

Comments

The first 13 rows include shortest k-superpatterns for k up to 5. These k-superpatterns are also optimal superpatterns. Optimal means the overall pattern density including patterns of all length is maximal among all permutations of [n]. How many more shortest superpatterns will be given by this sequence? The next will be expected in row 17.
Row n is a k-superpattern if row n of A371823 starts with 1!, 2!, ..., k!. If n also coincides with A342474(k), then row n is a shortest possible k-superpattern.
At time of sequence publication, all known rows agree up to cyclic shift with rows from A194832. This could indicate that A194832 will at least almost optimize the pattern density for permutations on the circle.
The above observations are accompanied by strong statistical arguments: because (1+sqrt(5))/2 has the simplest continued fraction expansion of any irrational number it will optimize asymptotically the pattern density in the permutations induced by it.

Examples

			The first 10 rows:
  1
  1,  2
  3,  1,  2
  3,  1,  4,  2
  2,  5,  3,  1,  4
  2,  5,  3,  6,  1,  4
  3,  6,  1,  4,  7,  2,  5
  2,  5,  8,  3,  6,  1,  4,  7
  6,  1,  9,  4,  7,  2,  5,  8,  3
  7,  2, 10,  5,  8,  3,  6,  1,  9,  4
		

Crossrefs

A371823 lists the number of different patterns of length k in row n.
Cf. A194832 (same rows cyclically shifted?).

Extensions

Edited by Peter Munn, Jul 09 2024
Previous Showing 41-49 of 49 results.