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.

A190249 Positions of 0 in A190248.

Original entry on oeis.org

2, 5, 10, 13, 18, 23, 26, 31, 34, 36, 39, 44, 47, 52, 57, 60, 65, 68, 73, 78, 81, 86, 89, 91, 94, 99, 102, 107, 112, 115, 120, 123, 128, 133, 136, 141, 146, 149, 154, 157, 162, 167, 170, 175, 178, 180, 183, 188, 191, 196, 201, 204, 209, 212, 217, 222, 225, 230, 233, 235, 238, 243, 246, 251, 256, 259, 264, 267, 272, 277, 280, 285, 290
Offset: 1

Views

Author

Clark Kimberling, May 06 2011

Keywords

Crossrefs

Programs

  • Mathematica
    u = GoldenRatio; v = u^2; w=u^3;
    f[n_] := Floor[n*u + n*v + n*w] - Floor[n*u] - Floor[n*v] - Floor[n*w]
    t = Table[f[n], {n, 1, 120}] (* A190248 *)
    Flatten[Position[t, 0]]      (* A190249 *)
    Flatten[Position[t, 1]]      (* A190250 *)
    Flatten[Position[t, 2]]      (* A190251 *)

A190251 Positions of 2 in A190248.

Original entry on oeis.org

3, 8, 11, 16, 21, 24, 29, 32, 37, 42, 45, 50, 53, 55, 58, 63, 66, 71, 76, 79, 84, 87, 92, 97, 100, 105, 110, 113, 118, 121, 126, 131, 134, 139, 142, 144, 147, 152, 155, 160, 165, 168, 173, 176, 181, 186, 189, 194, 197, 199, 202, 207, 210, 215, 220, 223, 228, 231, 236, 241, 244, 249, 254, 257, 262, 265, 270, 275, 278, 283, 286, 288
Offset: 1

Views

Author

Clark Kimberling, May 06 2011

Keywords

Crossrefs

Programs

  • Mathematica
    u = GoldenRatio; v = u^2; w=u^3;
    f[n_] := Floor[n*u + n*v + n*w] - Floor[n*u] - Floor[n*v] - Floor[n*w]
    t = Table[f[n], {n, 1, 120}] (* A190248 *)
    Flatten[Position[t, 0]]      (* A190249 *)
    Flatten[Position[t, 1]]      (* A190250 *)
    Flatten[Position[t, 2]]      (* A190251 *)

A190250 Positions of 1 in A190248.

Original entry on oeis.org

1, 4, 6, 7, 9, 12, 14, 15, 17, 19, 20, 22, 25, 27, 28, 30, 33, 35, 38, 40, 41, 43, 46, 48, 49, 51, 54, 56, 59, 61, 62, 64, 67, 69, 70, 72, 74, 75, 77, 80, 82, 83, 85, 88, 90, 93, 95, 96, 98, 101, 103, 104, 106, 108, 109, 111, 114, 116, 117, 119, 122, 124, 125, 127, 129, 130, 132, 135, 137, 138, 140, 143, 145, 148, 150, 151, 153, 156, 158, 159, 161
Offset: 1

Views

Author

Clark Kimberling, May 06 2011

Keywords

Comments

Numbers n such that 1/4 < {n*phi} < 3/4, where phi is the golden ratio (1+sqrt(5))/2 and { } denotes fractional part. - Burghard Herrmann, Nov 14 2017

Crossrefs

Programs

  • Mathematica
    u = GoldenRatio; v = u^2; w=u^3;
    f[n_] := Floor[n*u + n*v + n*w] - Floor[n*u] - Floor[n*v] - Floor[n*w]
    t = Table[f[n], {n, 1, 120}] (* A190248 *)
    Flatten[Position[t, 0]]      (* A190249 *)
    Flatten[Position[t, 1]]      (* A190250 *)
    Flatten[Position[t, 2]]      (* A190251 *)
  • PARI
    isok(n) = my(u=(1+sqrt(5))/2); floor(2*n+4*n*u)-floor(n*u)-floor(n+n*u)-floor(n+2*n*u) == 1; \\ Michel Marcus, Nov 14 2017

A190440 [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(golden ratio,4,0) and []=floor.

Original entry on oeis.org

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

Views

Author

Clark Kimberling, May 10 2011

Keywords

Comments

Write a(n)=[(bn+c)r]-b[nr]-[cr]. If r>0 and b and c are integers satisfying b>=2 and 0<=c<=b-1, then 0<=a(n)<=b. The positions of 0 in the sequence a are of interest, as are the position sequences for 1,2,...,b. These b+1 position sequences comprise a partition of the positive integers.
Examples:
(golden ratio,2,0): A078588, A005653, A005652
(golden ratio,2,1): A190427-A190430
(golden ratio,3,0): A140397-A190400
(golden ratio,3,1): A140431-A190435
(golden ratio,3,2): A140436-A190439

Crossrefs

Programs

  • Mathematica
    r = GoldenRatio;
    f[n_] := Floor[4*n*r] - 4*Floor[n*r];
    t = Table[f[n], {n, 1, 320}] (* A190440 *)
    Flatten[Position[t, 0]]  (* A190240 *)
    Flatten[Position[t, 1]]  (* A190249 *)
    Flatten[Position[t, 2]]  (* A190442 *)
    Flatten[Position[t, 3]]  (* A190443 *)
    Flatten[Position[t, 4]]  (* A190248 *)

Formula

a(n)=[4nr]-4[nr], where r=golden ratio.
Showing 1-4 of 4 results.