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 1-10 of 36 results. Next

A163528 The X-coordinate of the n-th point in the Peano curve A163334.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Comments

There is a 2-state automaton that accepts exactly those pairs (n,a(n)) where n is represented in base 9 and a(n) in base 3; see accompanying file a163528.pdf - Jeffrey Shallit, Aug 10 2023

Crossrefs

Formula

a(n) = A025581(A163335(n)) = A002262(A163337(n)) = A163325(A163332(n)).

Extensions

Name corrected by Kevin Ryde, Aug 28 2020

A163529 The Y-coordinate of the n-th point in the Peano curve A163334.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Comments

There is a 2-state automaton that accepts exactly those pairs (n,a(n)) where n is represented in base 9 and a(n) in base 3; see accompanying file a163529.pdf. - Jeffrey Shallit, Aug 10 2023

Crossrefs

Formula

a(n) = A002262(A163335(n)) = A025581(A163337(n)) = A163326(A163332(n)).

Extensions

Name corrected by Kevin Ryde, Aug 28 2020

A163335 Inverse permutation to A163334.

Original entry on oeis.org

0, 1, 3, 7, 4, 2, 5, 8, 12, 17, 23, 30, 22, 16, 11, 6, 10, 15, 21, 28, 36, 46, 37, 29, 38, 47, 57, 69, 58, 48, 59, 70, 82, 96, 83, 71, 60, 50, 41, 32, 40, 49, 39, 31, 24, 18, 13, 9, 14, 19, 25, 33, 26, 20, 27, 34, 42, 52, 43, 35, 44, 53, 63, 74, 86, 99, 85, 73, 62, 51, 61, 72
Offset: 0

Views

Author

Antti Karttunen, Jul 29 2009

Keywords

Comments

abs(A025581(a(n+1)) - A025581(a(n))) + abs(A002262(a(n+1)) - A002262(a(n))) = 1 for all n.

Crossrefs

Inverse: A163334. a(n) = A163329(A163332(n)). One-based version: A163339. See also A163337, A163358.

A163531 The square of the distance from the origin to the n-th point in the Peano curve A163334.

Original entry on oeis.org

0, 1, 4, 5, 2, 1, 4, 5, 8, 13, 20, 29, 26, 17, 10, 9, 16, 25, 36, 49, 64, 65, 50, 37, 40, 53, 68, 73, 58, 45, 52, 65, 80, 89, 74, 61, 50, 41, 34, 25, 32, 41, 34, 25, 18, 13, 10, 9, 16, 17, 20, 29, 26, 25, 36, 37, 40, 53, 50, 49, 64, 65, 68, 73, 80, 89, 74, 65, 58, 45, 52, 61
Offset: 0

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Crossrefs

See also: A163530, A163547.

Formula

a(n) = A000290(A163528(n)) + A000290(A163529(n)).

Extensions

Name corrected by Kevin Ryde, Aug 28 2020

A163534 The absolute direction (0=east, 1=south, 2=west, 3=north) of the Peano curve A163334 at point n.

Original entry on oeis.org

0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 3, 2, 2, 3, 0, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 1, 2, 2, 1, 0, 0, 1, 2, 2, 2, 2, 2, 3, 0, 0, 3, 2, 2, 2, 2, 2, 1, 0, 0, 1, 2, 2, 1, 0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 3, 2, 2, 3, 0, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 3, 2, 2, 3, 0, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 0, 0, 0, 3
Offset: 1

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Comments

Taking every ninth term gives the same sequence: (and similarly for all higher powers of 9 as well): a(n) = a(9*n).

Crossrefs

Cf. A163535 (transposed direction), A163536 (turn).

Programs

Formula

a(n) = A010873(A163532(n)+A163533(n)+abs(A163533(n))+3).
a(n) = A004442(A163535(n)).

Extensions

Name corrected by Kevin Ryde, Aug 29 2020

A163536 The relative direction (0=straight ahead, 1=turn right, 2=turn left) of the Peano curve A163334 at point n.

Original entry on oeis.org

0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 2, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 1, 1, 0, 2, 2, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 2, 0, 1, 1, 0, 2, 2, 0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 2, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 2, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 2
Offset: 1

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Comments

a(9*n) = a(81*n) for all n.

Crossrefs

Cf. A163534 (direction), A163537 (transposed relative).

Programs

Formula

a(n) = A163241((A163534(n+1)-A163534(n)) modulo 4).
a(n) = A014681(A163537(n)).

Extensions

Name corrected by Kevin Ryde, Aug 29 2020

A163532 The change in X-coordinate when moving from the n-1:th to the n-th point in the Peano curve A163334.

Original entry on oeis.org

0, 1, 1, 0, -1, -1, 0, 1, 1, 1, 1, 1, 0, -1, -1, 0, 1, 1, 1, 1, 1, 0, -1, -1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 0, -1, -1, -1, -1, -1, 0, 1, 1, 0, -1, -1, -1, -1, -1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 1, 1, 1, 0, -1, -1, 0, 1, 1, 1, 1, 1, 0, -1, -1, 0, 1, 1, 1, 1, 1, 0, -1, -1, 0
Offset: 0

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Crossrefs

A014578(n) = |a(n)|. These are the first differences of A163528. See also: A163533, A163534, A163536.

Formula

a(0)=0, a(n) = A163528(n) - A163528(n-1).

Extensions

Name corrected by Kevin Ryde, Aug 28 2020

A163533 The change in Y-coordinate when moving from the n-1:th to the n-th point in the Peano curve A163334.

Original entry on oeis.org

0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0
Offset: 0

Views

Author

Antti Karttunen, Aug 01 2009

Keywords

Crossrefs

These are the first differences of A163529. See also: A163532, A163534, A163536.

Formula

a(0)=0, a(n) = A163529(n) - A163529(n-1).

Extensions

Name corrected by Kevin Ryde, Aug 29 2020

A166041 Permutation of nonnegative integers: a(n) tells which integer is in the same position in the square array A163357 as where n is located in the array A163334.

Original entry on oeis.org

0, 1, 14, 13, 2, 3, 4, 7, 8, 11, 30, 29, 18, 17, 12, 15, 16, 19, 20, 21, 234, 233, 22, 23, 24, 25, 230, 229, 26, 27, 36, 37, 218, 217, 38, 39, 34, 33, 52, 53, 32, 35, 28, 31, 10, 9, 6, 5, 58, 57, 54, 55, 56, 59, 60, 61, 50, 49, 62, 63, 64, 67, 68, 69, 122, 123, 44, 47, 48
Offset: 0

Views

Author

Antti Karttunen, Oct 06 2009

Keywords

Comments

Fixed points are quite rare: A165465.

Examples

			The top left 9 X 9 corner of A163334:
   0  1  2 15 16 17 18 19 20
   5  4  3 14 13 12 23 22 21
   6  7  8  9 10 11 24 25 26
  47 46 45 44 43 42 29 28 27
  48 49 50 39 40 41 30 31 32
  53 52 51 38 37 36 35 34 33
  54 55 56 69 70 71 72 73 74
  59 58 57 68 67 66 77 76 75
  60 61 62 63 64 65 78 79 80
The top left 8 X 8 corner of A163357:
   0  1 14 15 16 19 20 21
   3  2 13 12 17 18 23 22
   4  7  8 11 30 29 24 25
   5  6  9 10 31 28 27 26
  58 57 54 53 32 35 36 37
  59 56 55 52 33 34 39 38
  60 61 50 51 46 45 40 41
  63 62 49 48 47 44 43 42
9 is in position (2,3) in A163334, while A163357(2,3) = 11. Thus a(9) = 11.
		

Crossrefs

Inverse: A166042. a(n) = A163357(A163335(n)) = A163359(A163337(n)). Cf. also A166043.

A163480 Row 0 of A163334 (column 0 of A163336).

Original entry on oeis.org

0, 1, 2, 15, 16, 17, 18, 19, 20, 141, 142, 143, 144, 145, 146, 159, 160, 161, 162, 163, 164, 177, 178, 179, 180, 181, 182, 1275, 1276, 1277, 1278, 1279, 1280, 1293, 1294, 1295, 1296, 1297, 1298, 1311, 1312, 1313, 1314, 1315, 1316, 1437, 1438, 1439
Offset: 0

Views

Author

Antti Karttunen, Jul 29 2009

Keywords

Crossrefs

Cf. A163481 (Y axis), A037314 (Z-order X axis).
Coordinates: A163528, A163529.

Programs

  • PARI
    a(n) = my(v=digits(n,3),s=Mod(0,2)); for(i=1,#v, if(s,v[i]+=6); s+=v[i]); fromdigits(v,9); \\ Kevin Ryde, Sep 29 2020

Formula

a(n) = A163332(A037314(n)). - Kevin Ryde, Sep 29 2020
Showing 1-10 of 36 results. Next