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.

A102565 a(n) = A102563(n) - A102564(n).

Original entry on oeis.org

0, 0, 1, -2, 1, -2, -1, 0, 1, -2, -1, 0, -1, 0, 1, -2, 1, -2, -1, 0, -1, 0, 1, -2, -1, 0, 1, -2, 1, -2, -1, 0, 1, -2, -1, 0, -1, 0, 1, -2, -1, 0, 1, -2, 1, -2, -1, 0, -1, 0, 1, -2, 1, -2, -1, 0, 1, -2, -1, 0, -1, 0, 1, -2, 1, -2, -1, 0, -1, 0, 1, -2, -1, 0, 1, -2, 1, -2, -1, 0, -1, 0, 1, -2, 1, -2, -1, 0, 1, -2, -1, 0, -1, 0, 1, -2, -1, 0, 1, -2, 1
Offset: 0

Views

Author

Paul Barry, Jan 14 2005

Keywords

Comments

It would appear that a(2n+1) = (-2)*A010060(n); a(4n+1) = (-2)*A010060(n); a(8n+1) = (-2)*A010060(n); a(2^n) = 0^n-1; a(2^n+1) = 3*0^n-2; a(2^(n+1)-1) = -(1-(-1)^n).

Crossrefs

A102563 a(n) = A000120(A001045(n)) - A001045(A000120(n)).

Original entry on oeis.org

0, 0, 0, 1, 1, 2, 2, 1, 3, 4, 4, 3, 5, 4, 4, 3, 7, 8, 8, 7, 9, 8, 8, 7, 11, 10, 10, 9, 11, 10, 10, 5, 15, 16, 16, 15, 17, 16, 16, 15, 19, 18, 18, 17, 19, 18, 18, 13, 23, 22, 22, 21, 23, 22, 22, 17, 25, 24, 24, 19, 25, 20, 20, 11, 31, 32, 32, 31, 33, 32, 32, 31, 35, 34, 34, 33, 35, 34
Offset: 0

Views

Author

Paul Barry, Jan 14 2005

Keywords

Crossrefs

Programs

  • Mathematica
    j[n_] := (2^n - (-1)^n)/3; s[n_] := DigitCount[n, 2, 1]; a[n_] := s[j[n]] - j[s[n]]; Array[a, 100, 0] (* Amiram Eldar, Jul 22 2023 *)

Formula

It would appear that a(2^(n+1)) = A000225(n).
a(2^(n+1)-1) = A001045(n).
a(2^(n+1)+1) = A000079(n).
a(2n+1) = n; a(4n+1) - a(2n+1) = n; a(8n+1) - a(4n+1) = 2n; a(8n+1) - a(2n+1) = 3n.
Showing 1-2 of 2 results.