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 1-2 of 2 results.

A187339 a(n) = floor((7+sqrt(5))*n/4); complement of A187330.

Original entry on oeis.org

2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25, 27, 30, 32, 34, 36, 39, 41, 43, 46, 48, 50, 53, 55, 57, 60, 62, 64, 66, 69, 71, 73, 76, 78, 80, 83, 85, 87, 90, 92, 94, 96, 99, 101, 103, 106, 108, 110, 113, 115, 117, 120, 122, 124, 126, 129, 131, 133, 136, 138, 140, 143, 145
Offset: 1

Views

Author

Clark Kimberling, Mar 08 2011

Keywords

Comments

A187339 and A187330 are a pair of Beatty sequences.

Crossrefs

Cf. A187330.

Programs

  • Mathematica
    Table[Floor[((7+5^(1/2))/4)n], {n,1,120}]

Formula

a(n)=floor((7+sqrt(5))*n/4).

A187907 Rank transform of the sequence floor((4 - sqrt(5))*n); complement of A187908.

Original entry on oeis.org

1, 3, 5, 7, 9, 11, 13, 15, 16, 19, 20, 23, 24, 26, 28, 30, 32, 34, 36, 38, 40, 41, 43, 46, 48, 49, 51, 53, 55, 57, 59, 61, 63, 64, 66, 68, 71, 73, 74, 76, 78, 80, 82, 84, 86, 88, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 139, 141, 143, 145, 147, 149, 151, 153, 155
Offset: 1

Views

Author

Clark Kimberling, Mar 15 2011

Keywords

Comments

See A187224. A187232(n) = A187907(n) for n=1..20; A187232(21)=39 and A187907(21)=40.

Crossrefs

Programs

  • Mathematica
    r=4-5^(1/2);
    seqA = Table[Floor[r*n], {n, 1, 220}] (* A187330 *)
    seqB = Table[n, {n, 1, 220}];  (* A000027 *)
    jointRank[{seqA_,
       seqB_}] := {Flatten@Position[#1, {_, 1}],
        Flatten@Position[#1, {_, 2}]} &[
      Sort@Flatten[{{#1, 1} & /@ seqA, {#1, 2} & /@ seqB}, 1]];
    limseqU =
    FixedPoint[jointRank[{seqA, #1[[1]]}] &,
       jointRank[{seqA, seqB}]][[1]] (* A187907 *)
    Complement[Range[Length[seqA]], limseqU]  (* A187908 *)
    (* Peter J. C. Moses, Mar 15 2011 *)
  • Maxima
    makelist(floor((4-sqrt(5))*n),n,1,100); /* Martin Ettl, Oct 17 2012 */
Showing 1-2 of 2 results.