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 1-6 of 6 results.

A373227 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 7; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 7.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 6, 8, 9, 10, 9, 11, 12, 13, 12, 14, 15, 16, 15, 17, 18, 17, 20, 18, 20, 22, 21, 21, 22, 26, 25, 23, 24, 28, 26, 29, 26, 31, 30, 32, 28, 34, 30, 37, 29, 38, 35, 37, 33, 39, 40, 38, 37, 42, 43, 40, 40, 44, 42, 47, 43, 44, 46, 51, 46, 46, 50, 50, 50, 51, 53, 50
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373228, A373229, A373230, A373231, A373232, A373233.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = If[0 < n < 8, n, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]];
Array[a, 100] (* Paolo Xausa, May 31 2024 *)

A373228 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 8; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 8.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 6, 9, 10, 11, 9, 12, 13, 14, 12, 15, 16, 17, 15, 18, 19, 17, 21, 18, 21, 23, 24, 19, 26, 23, 28, 24, 28, 27, 24, 31, 32, 28, 24, 36, 36, 33, 23, 37, 38, 40, 27, 39, 38, 42, 35, 41, 38, 43, 42, 44, 39, 44, 42, 51, 42, 45, 48, 47, 51, 44, 54, 48, 52, 49, 53
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373227, A373229, A373230, A373231, A373232, A373233.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = If[0 < n < 9, n, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]];
Array[a, 100] (* Paolo Xausa, May 31 2024 *)

A373229 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 9; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 9.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 6, 10, 11, 12, 9, 13, 14, 15, 12, 16, 17, 18, 15, 19, 20, 17, 22, 18, 22, 24, 25, 22, 21, 29, 28, 22, 24, 34, 27, 29, 28, 32, 27, 37, 33, 31, 34, 35, 36, 34, 36, 41, 36, 41, 36, 41, 43, 41, 43, 40, 48, 42, 41, 46, 46, 52, 43, 51, 46, 53, 51, 46, 56, 48
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373227, A373228, A373230, A373231, A373232, A373233.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = If[0 < n < 10, n, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]];
Array[a, 100] (* Paolo Xausa, May 31 2024 *)

A373231 Relative of Hofstadter Q-sequence: a(n) = 0 for n <= 0, a(n) = n for 1 <= n <= 11; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 11.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 6, 12, 13, 14, 9, 15, 16, 17, 12, 18, 19, 20, 15, 21, 22, 17, 24, 18, 24, 26, 27, 22, 21, 33, 30, 20, 29, 36, 27, 24, 36, 33, 31, 28, 42, 31, 33, 32, 48, 36, 25, 44, 44, 46, 22, 56, 38, 41, 40, 50, 43, 44, 43, 56, 49, 42, 45, 44, 67, 43, 47, 52
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
a(117) = 120. This is the smallest index for which a(n) > n. So, without the condition that a(n) = 0 for n <= 0, this sequence would be finite and have exactly 117 terms.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373227, A373228, A373229, A373230, A373232, A373233.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = Which[n < 1, 0, n < 12, n, True, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]]; Array[a, 100] (* Paolo Xausa, May 31 2024 *)

A373232 Relative of Hofstadter Q-sequence: a(n) = 0 for n <= 0, a(n) = n for 1 <= n <= 12; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 12.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 6, 13, 14, 15, 9, 16, 17, 18, 12, 19, 20, 21, 15, 22, 23, 17, 25, 18, 25, 27, 28, 22, 21, 35, 31, 19, 30, 31, 40, 25, 31, 27, 47, 31, 33, 24, 46, 35, 43, 24, 51, 32, 49, 33, 44, 37, 55, 40, 39, 46, 50, 44, 43, 54, 47, 40, 58, 50, 43, 57, 53
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
a(45) = 47. This is the smallest index for which a(n) > n. So, without the condition that a(n) = 0 for n <= 0, this sequence would be finite and have exactly 45 terms.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373227, A373228, A373229, A373230, A373231, A373233.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = Which[n < 1, 0, n < 13, n, True, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]]; Array[a, 100] (* Paolo Xausa, May 31 2024 *)

A373233 Relative of Hofstadter Q-sequence: a(n) = 0 for n <= 0, a(n) = n for 1 <= n <= 13; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 13.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 6, 14, 15, 16, 9, 17, 18, 19, 12, 20, 21, 22, 15, 23, 24, 17, 26, 18, 26, 28, 29, 22, 21, 37, 32, 18, 23, 38, 42, 24, 26, 39, 37, 37, 31, 33, 46, 32, 41, 38, 40, 36, 42, 49, 36, 46, 38, 56, 42, 48, 35, 62, 31, 52, 58, 59, 32, 43, 53, 82
Offset: 1

Views

Author

Nathan Fox, May 28 2024

Keywords

Comments

Similar to A278055 but with different starting values.
a(73) = 82. This is the smallest index for which a(n) > n. So, without the condition that a(n) = 0 for n <= 0, this sequence would be finite and have exactly 73 terms.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.

Links

Crossrefs

Cf. A005185, A278055, A373227, A373228, A373229, A373230, A373231, A373232.
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.

Programs

  • Mathematica
    a[n_] := a[n] = Which[n < 1, 0, n < 14, n, True, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]]; Array[a, 100] (* Paolo Xausa, May 31 2024 *)
Showing 1-6 of 6 results.

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