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 11-18 of 18 results.

A190457 a(n) = [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(golden ratio,4,3) and []=floor.

Original entry on oeis.org

3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 0, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 0, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 2, 4, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 4, 2, 1, 3, 2, 4, 3, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 4, 3
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
(golden ratio,4,c): A190440-A190461

Crossrefs

Programs

  • Mathematica
    r = GoldenRatio; b = 4; c = 3;
    f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r];
    t = Table[f[n], {n, 1, 320}]
    Flatten[Position[t, 0]]
    Flatten[Position[t, 1]]
    Flatten[Position[t, 2]]
    Flatten[Position[t, 3]]
    Flatten[Position[t, 4]]

A191330 Positions of 0 in A191329.

Original entry on oeis.org

4, 8, 10, 14, 20, 24, 26, 30, 36, 40, 46, 50, 52, 56, 62, 66, 68, 72, 76, 78, 82, 88, 92, 94, 98, 104, 108, 114, 118, 120, 124, 130, 134, 136, 140, 144, 146, 150, 156, 160, 162, 166, 172, 176, 178, 182, 186, 188, 192, 198, 202, 204, 208, 214, 218, 224, 228, 230, 234, 240, 244, 246, 250, 254, 256, 260, 266, 270, 272, 276, 282, 286
Offset: 1

Views

Author

Clark Kimberling, May 31 2011

Keywords

Comments

Examples

			A191329=(1,2,1,0,1,2,1,0,1,0,1,2,1,0,1...),
so that a(1)=4, a(2)=8, a(3)=10,...
		

Crossrefs

Programs

A302253 Positions of 3 in A190436.

Original entry on oeis.org

8, 21, 29, 42, 55, 63, 76, 97, 110, 118, 131, 144, 152, 165, 186, 199, 207, 220, 241, 254, 262, 275, 288, 296, 309, 330, 343, 351, 364, 377, 385, 398, 406, 419, 432, 440, 453, 474, 487, 495, 508, 521, 529, 542, 563, 576, 584, 597, 618, 631, 639, 652, 665, 673, 686, 707, 720, 728
Offset: 1

Views

Author

G. C. Greubel, Apr 04 2018

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
(golden ratio,4,c): A140440-A190461

Crossrefs

Programs

  • Mathematica
    r = GoldenRatio; b = 3; c = 2;
    f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r];
    t = Table[f[n], {n, 1, 500}] (* A190436 *)
    Flatten[Position[t, 0]] (* A190437 *)
    Flatten[Position[t, 1]] (* A190438 *)
    Flatten[Position[t, 2]] (* A190439 *)
    Flatten[Position[t, 3]] (* A302253 *)

A190451 [(bn+c)r]-b[nr]-[cr], where (r,b,c)=(golden ratio,4,2) and []=floor.

Original entry on oeis.org

2, 1, 3, 2, 0, 3, 1, 4, 2, 0, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 0, 2, 1, 3, 2, 0, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 0, 3, 1, 3, 2, 0, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 0, 2, 1, 3, 2, 0, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 0, 3, 1, 0, 2, 1, 3, 2, 0, 3, 1, 4, 2, 1, 3, 2, 0, 3, 1, 3, 2, 0, 3, 1, 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; b = 4; c = 2;
    f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r];
    t = Table[f[n], {n, 1, 320}]
    Flatten[Position[t, 0]]
    Flatten[Position[t, 1]]
    Flatten[Position[t, 2]]
    Flatten[Position[t, 3]]
    Flatten[Position[t, 4]]

A140401 Let S be the set of numbers formed from the sum of three distinct elements of A140398, or the sum of three distinct elements of A140399, or the sum of three distinct elements of A140400; sequence gives complement of S.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 18, 21, 23, 26, 29, 31, 34, 39, 42, 47, 55, 60, 68, 76, 81, 89, 102, 110, 123, 144, 157, 178, 199, 212, 233, 267, 288, 322, 377, 411, 466, 521, 555, 610, 699, 754, 843, 987
Offset: 1

Views

Author

Fred Lunnon, Jun 20 2008

Keywords

Crossrefs

Formula

It appears that this consists of the following numbers: { F_{k}, F_{k} + F_{k-3}, F_{k} + F_{k-2}, F_{2k} + F_{2k-5}, F_{2k+1} - F_{2k-4}, F_{2k+1} + F_{2k-3} }, where F (A000045) are the Fibonacci numbers and k and other subscripts are restricted to positive values.

A279933 Positive integers k such that {(k-1)*r} < 1/2, where r = golden ratio = (1 + sqrt(5))/2 and { } = fractional part.

Original entry on oeis.org

1, 3, 5, 6, 8, 11, 13, 14, 16, 19, 21, 24, 26, 27, 29, 32, 34, 35, 37, 39, 40, 42, 45, 47, 48, 50, 53, 55, 58, 60, 61, 63, 66, 68, 69, 71, 73, 74, 76, 79, 81, 82, 84, 87, 89, 90, 92, 94, 95, 97, 100, 102, 103, 105, 108, 110, 113, 115, 116, 118
Offset: 1

Views

Author

Clark Kimberling, Dec 23 2016

Keywords

Crossrefs

Cf. A005653, A279934 (complement).

Programs

  • Mathematica
    r = GoldenRatio;
    t = Table[If[FractionalPart[n r - r] < 1/2, 0, 1 ], {n, 1, 120}] (* {A078588(n-1)} *)
    Flatten[Position[t, 0]]  (* A279933 *)
    Flatten[Position[t, 1]]  (* A279934 *)

Formula

a(n) = 1 + A005653(n-1) for n > 1.

Extensions

New name from Jianing Song, Sep 12 2019

A183090 Tree generated by A005652, associated with numbers which are not the sum of two Fibonacci numbers.

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Dec 24 2010

Keywords

Comments

A permutation of the positive integers. See the comment at A183079.

Examples

			Top 5 rows:
  1;
  2;
  3,             4;
  6,      5,     8,      7;
  11, 12, 9, 10, 16, 15, 14, 13;
From row 3 to row 4: 3->(6,5) and 4->(8,7). For all such pairs, the 1st component is in L and the 2nd, in U.
		

Crossrefs

Formula

Let L(n)=A005652(n) and U(n)=A005653(n), these being complementary sequences, each comprising a maximal set no two of whose elements is a Fibonacci number.
The tree-array T(n,k) is then given by rows:
T(0,0)=1; T(1,0)=2;
T(n,2*j)=L(T(n-1,j));
T(n,2*j+1)=U(T(n-1,j));
for j=0,1,...,2^(n-1)-1, n>=2.

A367491 Lexicographically least increasing sequence, starting with 2, such that no two terms (possibly identical) sum to a Fibonacci number.

Original entry on oeis.org

2, 5, 7, 9, 10, 13, 15, 18, 20, 22, 23, 26, 28, 30, 31, 34, 36, 38, 39, 41, 43, 44, 47, 49, 52, 54, 56, 57, 60, 62, 64, 65, 68, 70, 73, 75, 77, 78, 81, 83, 85, 86, 89, 91, 93, 94, 96, 98, 99, 102, 104, 107, 109, 111, 112, 115, 117, 119, 120, 123, 125, 127, 128
Offset: 1

Views

Author

Jeffrey Shallit, Nov 20 2023

Keywords

Comments

There is an 8-state Fibonacci automaton that accepts the Zeckendorf representation of n if and only if n belongs to the sequence.

Examples

			6 is not in the sequence, since if it were, 6+2 = 8, a Fibonacci number.
		

Crossrefs

Cf. A005652, A005653. This sequence allows the same term to be used twice in the sum, whereas in the other two sequences, the terms must be distinct.
Previous Showing 11-18 of 18 results.