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 1-7 of 7 results.

A118761 Fixed points of permutations A118757, A118758, A118759 and A118760.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 119, 138, 157, 176, 195, 310, 339, 358, 377, 396, 559, 578, 597, 779, 798, 999, 3130
Offset: 1

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Author

Reinhard Zumkeller, May 01 2006

Keywords

Comments

A118757(a(n)) = A118758(a(n)) = A118759(a(n)) = A118760(a(n)) = a(n);
a(n) = A024657(n-1) = A102491(n) for n<=50.

Crossrefs

Cf. A118767.

A118760 A118758(A118758(n)).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 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, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 118, 108, 127, 126
Offset: 0

Views

Author

Reinhard Zumkeller, May 01 2006

Keywords

Comments

Inverse integer permutation of A118759; a(n)=A118759(n) for n<100; A118757(a(n))=a(A118757(n))=A118758(n).

Crossrefs

Cf. A118759.

A118757 Permutation of the natural numbers such that the Levenshtein distance between decimal representations of successive terms is 1, and a(n+1) is the largest such m < a(n) if it exists, or else the smallest such m > a(n); a(0) = 0.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 79, 78, 77
Offset: 0

Views

Author

Reinhard Zumkeller, May 01 2006

Keywords

Comments

a(n) = A003100(n) for n <= 100, a(100) = A003100(100) = 190, but a(101) = 180, A003100(101) = 191.
A118763 is the lexicographically smallest permutation with LevenshteinDistance[Base10](a(n),a(n+1)) = 1. - M. F. Hasler, Sep 12 2018

Crossrefs

Cf. A118763.
Iterated twice: A118759(n) := a(a(n)).
Fixed points: A118761 = { n | n = a(n) }.
Inverse: A118758.
First difference: A118762(n) := a(n+1) - a(n).

Formula

a(n+1) = if U(n) is empty then Min(V(n)) else Max(U(n)), where the sets U and V are defined as: U(m) = {x < a(m) : LD10(a(m),x) = 1 and a(k) <> x for 0 <= k < m}, V(m) = {x > a(m) | LD10(a(m),x) = 1 and a(k) <> x for 0 <= k < m} with LD10 = Levenshtein distance in decimal representations of natural numbers.
a(n) = A118758(n) (self-inverse) for n < 100.

Extensions

Correct definition and other edits by M. F. Hasler, Sep 12 2018

A118764 Inverse of A118763.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 10, 21, 22, 23, 24, 25, 26, 27, 28, 20, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 30, 41, 42, 43, 44, 45, 46, 47, 48, 40, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 50, 61, 62, 63, 64, 65, 66, 67, 68, 60, 69, 71, 72, 73
Offset: 0

Views

Author

Reinhard Zumkeller, May 01 2006

Keywords

Comments

Permutation of the natural numbers with fixed points A118767: a(A118767(n))=A118767(n);
A118766(n) = a(a(n)).

Crossrefs

Cf. A118758.

Programs

  • Mathematica
    (* first do Mmca in A118763, then *) Flatten@ Table[Position[s, n], {n, 0, 100}] - 1 (* Robert G. Wilson v, Sep 22 2016 *)

A118759 A118757(A118757(n)).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 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, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 189
Offset: 0

Views

Author

Reinhard Zumkeller, May 01 2006

Keywords

Comments

Inverse integer permutation of A118760; a(n)=A118760(n)=n for n<100, but a(100)=189 and A118760(100)=118; A118758(a(n))=a(A118758(n))=A118757(n).

Crossrefs

Cf. A118760.

Extensions

More terms from Charles R Greathouse IV, Sep 18 2015

A261725 Lexicographically earliest sequence of distinct terms such that the absolute difference of two successive terms is a power of 10, and can be computed without carry.

Original entry on oeis.org

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

Views

Author

Paul Tek, Aug 30 2015

Keywords

Comments

In base 10, two successive terms have the same representation, except for one position, where the digits differ from exactly one unit. This difference can occur on a leading zero.
Conjectured to be a permutation of the nonnegative integers. See A261729 for putative inverse.
a(n) = A003100(n) for n < 101, but a(101) = 180, A003100(101) = 191.
a(n) = A118757(n) for n < 201, but a(201) = 281, A118757(201) = 290.
a(n) = A118758(n) for n < 100, but a(100) = 190, A118758(100) = 109.
a(n) = A174025(n) for n < 100, but a(100) = 190, A174025(100) = 199.
a(n) = A261729(n) for n < 100, but a(100) = 190, A261729(100) = 109.

Crossrefs

Cf. A003100, A118757, A118763, A163252, A261729 (putative inverse).

Programs

  • Perl
    See Links section.

A261729 Putative inverse of conjectured permutation in A261725.

Original entry on oeis.org

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

Views

Author

Paul Tek, Aug 30 2015

Keywords

Comments

a(n) = A003100(n) for n < 100, but a(100) = 109, A003100(100) = 190.
a(n) = A118757(n) for n < 100, but a(100) = 109, A118757(100) = 190.
a(n) = A118758(n) for n < 201, but a(201) = 209, A118758(201) = 211.
a(n) = A174025(n) for n < 100, but a(100) = 109, A174025(100) = 199.
a(n) = A261725(n) for n < 100, but a(100) = 109, A261725(100) = 190.

Crossrefs

Cf. A261725.
Showing 1-7 of 7 results.