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.

A214980 Positions of zeros in A214979.

Original entry on oeis.org

1, 2, 3, 5, 6, 8, 9, 10, 16, 17, 24, 26, 27, 28, 45, 46, 71, 73, 74, 75, 121, 122, 194, 196, 197, 198, 320, 321, 516, 518, 519, 520, 841, 842, 1359, 1361, 1362, 1363, 2205, 2206, 3566, 3568, 3569, 3570, 5776, 5777, 9344, 9346, 9347, 9348, 15125
Offset: 1

Views

Author

Clark Kimberling, Oct 22 2012

Keywords

Comments

Let U(n) and V(n) be the number of terms in the Lucas representations and Zeckendorf (Fibonacci) representations, respectively, of all the numbers 1,2,...,n. Then A214980 is the sequence of zeros of the sequence A214979(n) = V(n) - U(n). It is conjectured at A214979 that A214980 is infinite.

Crossrefs

Programs

  • Mathematica
    (See the program at A214979.)

A214977 Number of terms in Lucas representations of 1,2,...,n.

Original entry on oeis.org

1, 2, 3, 4, 6, 8, 9, 11, 13, 15, 16, 18, 20, 22, 24, 27, 30, 31, 33, 35, 37, 39, 42, 45, 47, 50, 53, 56, 57, 59, 61, 63, 65, 68, 71, 73, 76, 79, 82, 84, 87, 90, 93, 96, 100, 104, 105, 107, 109, 111, 113, 116, 119, 121, 124, 127, 130, 132, 135, 138, 141, 144
Offset: 1

Views

Author

Clark Kimberling, Oct 22 2012

Keywords

Comments

See the conjecture at A214979.

Examples

			n..Lucas(n)..# terms...A214977(n)
1..1.........1.........1
2..2.........1.........2
3..3.........1.........3
4..4.........1.........4
5..4+1.......2.........6
6..4+2.......2.........8
7..7.........1.........9
8..7+1.......2.........11
9..7+2.......2.........13
		

Crossrefs

Programs

  • Mathematica
    z = 200; s = Reverse[Sort[Table[LucasL[n - 1], {n, 1, 70}]]]; t1 = Map[Length[Select[Reap[FoldList[(Sow[Quotient[#1, #2]]; Mod[#1, #2]) &, #, s]][[2,1]], # > 0 &]] &, Range[z]]; u[n_] := Sum[t1[[k]], {k, 1, n}]; u1 = Table[u[n], {n, 1, z}]
    (* Peter J. C. Moses, Oct 18 2012 *)

A214981 Number of terms in the greedy Lucas-and-Fibonacci representations of 1,2,...,n; partial sums of A214973.

Original entry on oeis.org

1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 14, 16, 17, 19, 21, 23, 25, 26, 28, 30, 31, 33, 35, 37, 39, 41, 44, 46, 47, 49, 51, 53, 55, 56, 58, 60, 62, 64, 66, 69, 71, 73, 76, 79, 81, 84, 85, 87, 89, 91, 93, 95, 98, 100, 101, 103, 105, 107, 109, 111, 114, 116, 118, 121, 124
Offset: 1

Views

Author

Clark Kimberling, Oct 22 2012

Keywords

Comments

For comparison with Zeckendorf (Fibonacci) representations, it is conjectured that the limit of A179180(n)/A214981(n) exists and is between 1.2 and 1.4.

Examples

			The basis is B = (1,2,3,4,5,7,8,11,13,18,21,29,34,47,55,...), composed of Fibonacci numbers and Lucas numbers. Representations of positive integers using the greedy algorithm on B:
   n  repres.   # terms  a(n)
   1   1        1        1
   2   2        1        2
   3   3        1        3
   4   4        1        4
   5   5        1        5
   6   5+1      2        7
   7   7        1        8
   8   8        1        9
   9   8+1      2       11
  10   8+2      2       13
  27   21+5+1   3       44
		

Crossrefs

Programs

  • Mathematica
    (See the program at A214973.)

Extensions

Edited by Clark Kimberling, Jun 13 2020

A179180 Partial sums of A007895.

Original entry on oeis.org

0, 1, 2, 3, 5, 6, 8, 10, 11, 13, 15, 17, 20, 21, 23, 25, 27, 30, 32, 35, 38, 39, 41, 43, 45, 48, 50, 53, 56, 58, 61, 64, 67, 71, 72, 74, 76, 78, 81, 83, 86, 89, 91, 94, 97, 100, 104, 106, 109, 112, 115, 119, 122, 126, 130, 131, 133, 135, 137, 140, 142, 145
Offset: 0

Views

Author

Walt Rorie-Baety, Jun 30 2010

Keywords

Comments

Total number of summands in Zeckendorf representations of all the numbers 1,2,...,n (for n>0); see the conjecture at A214979. - Clark Kimberling, Oct 23 2012

Examples

			For n = 6, a(n) = 1+1+1+2+1+2 = 8.
		

Crossrefs

Programs

  • Mathematica
    s = Reverse[Table[Fibonacci[n + 1], {n, 1, 70}]];
    t2 = Map[Length[Select[Reap[FoldList[(Sow[Quotient[#1, #2]]; Mod[#1, #2]) &, #, s]][[2, 1]], # > 0 &]] &, Range[z]]; v[n_] := Sum[t2[[k]], {k, 1, n}];
    v1 = Table[v[n], {n, 1, z}]
    (* Peter J. C. Moses, Oct 18 2012 *)
    DigitCount[Select[Range[0, 500], BitAnd[#, 2*#] == 0&], 2, 1] // Accumulate (* Jean-François Alcover, Jan 25 2018 *)

Formula

a(n) ~ c * n * log(n), where c = (phi-1)/(sqrt(5)*log(phi)) = 0.574369... and phi is the golden ratio (A001622) (Ballot, 2013). - Amiram Eldar, Dec 09 2021

Extensions

Corrected term a(17); the working list of the terms were not in order. Walt Rorie-Baety, Jun 30 2010
Extended by Clark Kimberling, Oct 23 2012
Showing 1-4 of 4 results.