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 1-4 of 4 results.

A140758 a(n) = floor(n*Pi/2).

Original entry on oeis.org

0, 1, 3, 4, 6, 7, 9, 10, 12, 14, 15, 17, 18, 20, 21, 23, 25, 26, 28, 29, 31, 32, 34, 36, 37, 39, 40, 42, 43, 45, 47, 48, 50, 51, 53, 54, 56, 58, 59, 61, 62, 64, 65, 67, 69, 70, 72, 73, 75, 76, 78, 80, 81, 83, 84, 86, 87, 89, 91, 92, 94, 95, 97, 98, 100, 102, 103, 105
Offset: 0

Views

Author

Reinhard Zumkeller, May 27 2008

Keywords

Comments

Beatty sequence for Pi/2; complement of A108589; not the same as A093610: a(23)=36 <> A093610(23)=35.

Examples

			For n = 5, 5*(Pi/2) approximately equals 7.854, and floor(7.854) = 7.
		

Crossrefs

Programs

  • Magma
    R:= RealField(40); [Floor(n*Pi(R)/2): n in [0..80]]; // G. C. Greubel, Oct 21 2023
    
  • Mathematica
    Floor[Pi*Range[0,80]/2] (* G. C. Greubel, Oct 21 2023 *)
  • Python
    import math
    x=0
    while x < 36001:
        y = math.radians(x)
        z = math.trunc(y)
        print(z, end=", ")
        x += 90
    # Mick Purcell (mickpurcell(AT)gmail.com), Oct 05 2009
    
  • SageMath
    [floor(n*pi/2) for n in range(81)] # G. C. Greubel, Oct 21 2023

Extensions

0 added by Mick Purcell (mickpurcell(AT)gmail.com), Oct 05 2009

A108591 Self-inverse integer permutation induced by Beatty sequences for Pi and Pi/(Pi-1).

Original entry on oeis.org

3, 6, 1, 9, 12, 2, 15, 18, 4, 21, 25, 5, 28, 31, 7, 34, 37, 8, 40, 43, 10, 47, 50, 53, 11, 56, 59, 13, 62, 65, 14, 69, 72, 16, 75, 78, 17, 81, 84, 19, 87, 91, 20, 94, 97, 100, 22, 103, 106, 23, 109, 113, 24, 116, 119, 26, 122, 125, 27, 128, 131, 29, 135, 138, 30, 141, 144
Offset: 1

Views

Author

Reinhard Zumkeller, Jun 11 2005

Keywords

Crossrefs

Formula

a(A022844(n))=A054386(n) and a(A054386(n))=A022844(n).

Extensions

a(53)/a(54) joined by Georg Fischer, May 24 2022

A108589 a(n) = floor(n*Pi/(Pi-2)).

Original entry on oeis.org

2, 5, 8, 11, 13, 16, 19, 22, 24, 27, 30, 33, 35, 38, 41, 44, 46, 49, 52, 55, 57, 60, 63, 66, 68, 71, 74, 77, 79, 82, 85, 88, 90, 93, 96, 99, 101, 104, 107, 110, 112, 115, 118, 121, 123, 126, 129, 132, 134, 137, 140, 143, 145, 148, 151, 154, 156, 159, 162, 165, 167
Offset: 1

Views

Author

Reinhard Zumkeller, Jun 11 2005

Keywords

Comments

Beatty sequence for Pi/(Pi-2); complement of A140758.

Crossrefs

Programs

  • Magma
    R:= RealField(40); [Floor(n*Pi(R)/(Pi(R)-2)): n in [1..60]]; // G. C. Greubel, Oct 21 2023
    
  • Maple
    A108589:=n->floor(n*Pi/(Pi-2)); seq(A108589(n), n=1..50); # Wesley Ivan Hurt, Apr 19 2014
  • Mathematica
    With[{c=Pi/(Pi-2)},Floor[c*Range[70]]] (* Harvey P. Dale, Apr 19 2014 *)
  • SageMath
    [floor(n*pi/(pi-2)) for n in range(1,61)] # G. C. Greubel, Oct 21 2023

A108592 Self-inverse integer permutation induced by Beatty sequences for 2*Pi and 2*Pi/(2*Pi-1).

Original entry on oeis.org

6, 12, 18, 25, 31, 1, 37, 43, 50, 56, 62, 2, 69, 75, 81, 87, 94, 3, 100, 106, 113, 119, 125, 131, 4, 138, 144, 150, 157, 163, 5, 169, 175, 182, 188, 194, 7, 201, 207, 213, 219, 226, 8, 232, 238, 245, 251, 257, 263, 9, 270, 276, 282, 289, 295, 10, 301, 307, 314, 320, 326, 11, 333, 339, 345, 351, 358, 364, 13, 370
Offset: 1

Views

Author

Reinhard Zumkeller, Jun 11 2005

Keywords

Crossrefs

Programs

  • PARI
    a30(n) = floor(n*2*Pi);
    a86(n) = floor(2*n*Pi/(2*Pi-1));
    lista(nn) = {my(vb = vector(nn, n, a30(n))); my(vc = vector(nn, n, a86(n))); my(va = vector(nn)); for (n=1, nn, if (vb[n] <= nn, va[vb[n]] = vc[n]); if (vc[n] <= nn, va[vc[n]] = vb[n]);); va;} \\ Michel Marcus, May 25 2022

Formula

a(A038130(n))=A108586(n) and a(A108586(n))=A038130(n).

Extensions

Four terms corrected by Georg Fischer and Michel Marcus, May 25 2022
Showing 1-4 of 4 results.