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.

A287475 a(0) = 0; a(1) = 1; a(2*n) = a(n), a(2*n+1) = a(n-a(n)) + a(n-a(n+1)).

Original entry on oeis.org

0, 1, 1, 0, 1, 2, 0, 1, 1, 1, 2, 2, 0, 2, 1, 0, 1, 2, 1, 2, 2, 2, 2, 3, 0, 2, 2, 2, 1, 3, 0, 1, 1, 1, 2, 1, 1, 3, 2, 4, 2, 2, 2, 4, 2, 4, 3, 5, 0, 2, 2, 6, 2, 0, 2, 4, 1, 4, 3, 5, 0, 3, 1, 0, 1, 2, 1, 2, 2, 2, 1, 4, 1, 2, 3, 3, 2, 3, 4, 4, 2, 4, 2, 8, 2, 4, 4, 6, 2, 4, 4, 4, 3, 6, 5, 7, 0, 3, 2, 10, 2
Offset: 0

Views

Author

Ilya Gutkovskiy, May 25 2017

Keywords

Comments

A variation on Hofstadter's Q-sequence and Stern's diatomic sequence.

Links

Crossrefs

Cf. A002487, A005185, A287476, A287477.

Programs

  • Mathematica
    a[0] = 0; a[1] = 1; a[n_] := If[EvenQ[n], a[n/2], a[(n - 1)/2 - a[(n - 1)/2]] + a[(n - 1)/2 - a[(n + 1)/2]]]; Table[a[n], {n, 0, 100}]

A287477 a(0) = 0; a(1) = 1; a(2*n) = n - a(a(n)), a(2*n+1) = a(n-a(n)) + a(n-a(n+1)).

Original entry on oeis.org

0, 1, 0, 1, 2, 1, 2, 1, 4, 1, 4, 3, 6, 3, 6, 3, 6, 3, 8, 5, 8, 3, 10, 5, 10, 3, 12, 5, 12, 7, 14, 7, 14, 7, 16, 7, 14, 7, 18, 9, 16, 9, 20, 11, 18, 9, 22, 11, 20, 9, 24, 13, 20, 9, 26, 13, 22, 9, 28, 13, 24, 11, 30, 13, 26, 11, 32, 15, 28, 13, 34, 15, 30, 17, 36, 19, 30, 15, 38, 19, 34, 17, 40, 17, 34, 17
Offset: 0

Views

Author

Ilya Gutkovskiy, May 25 2017

Keywords

Comments

A variation on Hofstadter's G-sequence, Hofstadter's Q-sequence and Stern's diatomic sequence.

Links

Crossrefs

Cf. A002487, A005185, A005206, A287475, A287476.

Programs

  • Mathematica
    a[0] = 0; a[1] = 1; a[n_] := If[EvenQ[n], n/2 - a[a[n/2]], a[(n - 1)/2 - a[(n - 1)/2]] + a[(n - 1)/2 - a[(n + 1)/2]]]; Table[a[n], {n, 0, 85}]

A287597 a(0) = 0, a(1) = 1; a(2*n) = n - a(a(n)), a(2*n+1) = a(a(n)) + a(a(n+1)).

Original entry on oeis.org

0, 1, 0, 1, 2, 1, 2, 1, 4, 1, 4, 1, 6, 1, 6, 3, 6, 3, 8, 3, 8, 3, 10, 3, 10, 3, 12, 3, 12, 3, 14, 3, 14, 3, 16, 5, 14, 5, 18, 5, 16, 5, 20, 5, 18, 5, 22, 5, 20, 5, 24, 7, 20, 7, 26, 7, 22, 7, 28, 7, 24, 7, 30, 7, 26, 7, 32, 7, 28, 7, 34, 7, 30, 7, 36, 9, 30, 9, 38, 7, 34, 7, 40, 9, 34, 9
Offset: 0

Views

Author

Ilya Gutkovskiy, May 27 2017

Keywords

Comments

A variation on Hofstadter's G-sequence and Stern's diatomic sequence.

Links

Crossrefs

Cf. A002487, A005206, A046698, A287475, A287476, A287477.

Programs

  • Mathematica
    a[0] = 0; a[1] = 1; a[n_] := If[EvenQ[n], n/2 - a[a[n/2]], a[a[(n - 1)/2]] + a[a[(n + 1)/2]]]; Table[a[n], {n, 0, 85}]

Formula

a(2*n) + a(2*n+1) + a(2*n+2) = 2*n + 1 (from definition).

A287601 a(0) = a(1) = 1; a(2*n) = n - a(a(n)), a(2*n+1) = a(a(n)) + a(n-a(n)).

Original entry on oeis.org

1, 1, 0, 2, 1, 1, 3, 1, 3, 3, 4, 2, 4, 4, 6, 4, 6, 3, 7, 5, 9, 4, 11, 3, 11, 4, 12, 4, 11, 6, 14, 3, 13, 7, 15, 8, 17, 3, 18, 7, 17, 5, 20, 4, 20, 4, 21, 11, 22, 6, 24, 5, 22, 10, 26, 4, 26, 5, 26, 6, 24, 12, 29, 13, 28, 9, 32, 13, 30, 9, 32, 7, 33, 8, 35, 17, 31, 16, 38, 14, 37, 6, 40, 18, 33, 20
Offset: 0

Views

Author

Ilya Gutkovskiy, May 27 2017

Keywords

Comments

A variation on Hofstadter's G-sequence and Hofstadter-Conway $10000 sequence.

Links

Crossrefs

Cf. A004001, A005206, A287475, A287476, A287477, A287597.

Programs

  • Mathematica
    a[0] = 1; a[1] = 1; a[n_] := If[EvenQ[n], n/2 - a[a[n/2]], a[a[(n - 1)/2]] + a[(n - 1)/2 - a[(n - 1)/2]]]; Table[a[n], {n, 0, 85}]
Showing 1-4 of 4 results.

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