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.

A127915 a(1)=1, a(2)=2. For n >= 3, a(n) is the smallest positive integer not occurring earlier in the sequence such that floor(a(n)/a(n-1)) does not equal floor(a(n-1)/a(n-2)).

Original entry on oeis.org

1, 2, 3, 6, 4, 5, 10, 7, 8, 16, 9, 11, 22, 12, 13, 26, 14, 15, 30, 17, 18, 36, 19, 20, 40, 21, 23, 46, 24, 25, 50, 27, 28, 56, 29, 31, 62, 32, 33, 66, 34, 35, 70, 37, 38, 76, 39, 41, 82, 42, 43, 86, 44, 45, 90, 47, 48, 96, 49, 51, 102, 52, 53, 106, 54, 55, 110, 57, 58, 116, 59
Offset: 1

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Author

Leroy Quet, Apr 06 2007

Keywords

Comments

This sequence is a permutation of the positive integers.

Programs

  • Mathematica
    a = {1, 2}; For[n = 3, n < 60, n++, i = 3; While[Length[Intersection[{i}, a]] == 1 || Floor[i/a[[ -1]]] == Floor[a[[ -1]]/a[[ -2]]], i++ ]; AppendTo[a, i]]; a (* Stefan Steinerberger, Oct 16 2007 *)

Extensions

More terms from Stefan Steinerberger, Oct 16 2007