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.

Previous Showing 11-19 of 19 results.

A245345 Sum of digits of n written in fractional base 9/2.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 2, 3, 4, 5, 6, 7, 8, 9, 10, 4, 5, 6, 7, 8, 9, 10, 11, 12, 6, 7, 8, 9, 10, 11, 12, 13, 14, 8, 9, 10, 11, 12, 13, 14, 15, 16, 3, 4, 5, 6, 7, 8, 9, 10, 11, 5, 6, 7, 8, 9, 10, 11, 12, 13, 7, 8, 9, 10, 11, 12, 13, 14, 15, 9, 10, 11, 12
Offset: 0

Views

Author

Tom Edgar, Jul 18 2014

Keywords

Comments

The base 9/2 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 9/2 the number 19 is represented by 41 and so a(19) = 4 + 1 = 5.

Links

Crossrefs

Cf. A000120, A007953, A024650, A053830, A244040.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[2 * Floor[n/9]] + Mod[n, 9]]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\9 * 2) + n % 9); \\ Amiram Eldar, Aug 02 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(9,2,i) for i in [0..100]]

Formula

a(n) = A007953(A024650(n)).

A245346 Sum of digits of n in fractional base 10/3.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 7, 8, 9
Offset: 0

Views

Author

James Van Alstine, Jul 18 2014

Keywords

Comments

The base 10/3 expansion is unique, and thus the sum of digits function is well-defined.

Examples

			In base 10/3 the number 11 is represented by 31 and so a(11) = 3 + 1 = 4.

Links

Crossrefs

Cf. A007953, A024658.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[3 * Floor[n/10]] + Mod[n, 10]]; Array[a, 100, 0] (* Amiram Eldar, Aug 04 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\10 * 3) + n % 10); \\ Amiram Eldar, Aug 04 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(10,3,y) for y in [0..200]]

Formula

a(n) = A007953(A024658(n)). - Amiram Eldar, Aug 04 2025

A245347 Sum of digits of n written in fractional base 8/3.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 3, 4, 5, 6, 7, 8, 9, 10, 6, 7, 8, 9, 10, 11, 12, 13, 4, 5, 6, 7, 8, 9, 10, 11, 7, 8, 9, 10, 11, 12, 13, 14, 10, 11, 12, 13, 14, 15, 16, 17, 8, 9, 10, 11, 12, 13, 14, 15, 11, 12, 13, 14, 15, 16, 17, 18, 4, 5, 6, 7, 8, 9, 10, 11, 7, 8, 9
Offset: 0

Views

Author

Hailey R. Olafson, Jul 18 2014

Keywords

Comments

The base 8/3 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 8/3 the number 14 is represented by 36 and so a(14) = 3 + 6 = 9.

Links

Crossrefs

Cf. A000120, A007953, A024645, A053829, A244040.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[3 * Floor[n/8]] + Mod[n, 8]]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\8 * 3) + n % 8); \\ Amiram Eldar, Aug 02 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(8,3,w) for w in [0..200]]

Formula

a(n) = A007953(A024645(n)).

A245349 Sum of digits of n written in fractional base 7/4.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 4, 5, 6, 7, 8, 9, 10, 5, 6, 7, 8, 9, 10, 11, 9, 10, 11, 12, 13, 14, 15, 7, 8, 9, 10, 11, 12, 13, 11, 12, 13, 14, 15, 16, 17, 12, 13, 14, 15, 16, 17, 18, 7, 8, 9, 10, 11, 12, 13, 11, 12, 13, 14, 15, 16, 17, 12, 13, 14, 15, 16, 17
Offset: 0

Views

Author

James Van Alstine, Jul 18 2014

Keywords

Comments

The base 7/4 expansion is unique, and thus the sum of digits function is well-defined.

Examples

			In base 7/4 the number 7 is represented by 40 and so a(7) = 4 + 0 = 4.

Links

Crossrefs

Cf. A024641, A053828, A007953.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[4 * Floor[n/7]] + Mod[n, 7]]; Array[a, 100, 0] (* Amiram Eldar, Jul 31 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\7 * 4) + n % 7); \\ Amiram Eldar, Jul 31 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(7,4,y) for y in [0..200]]

Formula

a(n) = A007953(A024641(n)). - Amiram Eldar, Jul 31 2025

A245350 Sum of digits of n written in fractional base 9/4.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 4, 5, 6, 7, 8, 9, 10, 11, 12, 8, 9, 10, 11, 12, 13, 14, 15, 16, 7, 8, 9, 10, 11, 12, 13, 14, 15, 11, 12, 13, 14, 15, 16, 17, 18, 19, 10, 11, 12, 13, 14, 15, 16, 17, 18, 14, 15, 16, 17, 18, 19, 20, 21, 22, 8, 9, 10, 11, 12, 13, 14, 15
Offset: 0

Views

Author

Tom Edgar, Jul 18 2014

Keywords

Comments

The base 9/4 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 9/4 the number 16 is represented by 47 and so a(16) = 4 + 7 = 11.

Links

Crossrefs

Cf. A000120, A007953, A024652, A053830, A244040.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[4 * Floor[n/9]] + Mod[n, 9]]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\9 * 4) + n % 9); \\ Amiram Eldar, Aug 02 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(9,4,i) for i in [0..100]]

Formula

a(n) = A007953(A024652(n)).

A245351 Sum of digits of n written in fractional base 10/7.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 21, 22, 23, 24, 25, 26, 27, 28
Offset: 0

Views

Author

Hailey R. Olafson, Jul 18 2014

Keywords

Comments

The base 10/7 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 10/7 the number 14 is represented by 74 and so a(14) = 7 + 4 = 11.

Links

Crossrefs

Cf. A000120, A007953, A024662, A244040.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[7 * Floor[n/10]] + Mod[n, 10]]; Array[a, 100, 0] (* Amiram Eldar, Aug 04 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\10 * 7) + n % 10); \\ Amiram Eldar, Aug 04 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(10,7,w) for w in [0..200]]

Formula

a(n) = A007953(A024662(n)).

A245352 Sum of digits of n written in fractional base 7/5.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 5, 6, 7, 8, 9, 10, 11, 8, 9, 10, 11, 12, 13, 14, 9, 10, 11, 12, 13, 14, 15, 14, 15, 16, 17, 18, 19, 20, 13, 14, 15, 16, 17, 18, 19, 16, 17, 18, 19, 20, 21, 22, 13, 14, 15, 16, 17, 18, 19, 18, 19, 20, 21, 22, 23, 24, 19, 20, 21, 22, 23, 24
Offset: 0

Views

Author

Hailey R. Olafson, Jul 18 2014

Keywords

Comments

The base 7/5 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 7/5 the number 14 is represented by 530 and so a(14) = 5 + 3 + 0 = 8.

Links

Crossrefs

Cf. A007953, A000120, A244040, A024642, A053828.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[5 * Floor[n/7]] + Mod[n, 7]]; Array[a, 100, 0] (* Amiram Eldar, Jul 31 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\7 * 5) + n % 7); \\ Amiram Eldar, Jul 31 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(7,5,w) for w in [0..200]]

Formula

a(n) = A007953(A024642(n)).

A245353 Sum of digits of n written in fractional base 9/7.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 7, 8, 9, 10, 11, 12, 13, 14, 15, 12, 13, 14, 15, 16, 17, 18, 19, 20, 15, 16, 17, 18, 19, 20, 21, 22, 23, 16, 17, 18, 19, 20, 21, 22, 23, 24, 23, 24, 25, 26, 27, 28, 29, 30, 31, 22, 23, 24, 25, 26, 27, 28, 29, 30, 27, 28, 29, 30, 31
Offset: 0

Views

Author

Hailey R. Olafson, Jul 18 2014

Keywords

Comments

The base 9/7 expansion is unique and thus the sum of digits function is well-defined.

Examples

			In base 9/7 the number 14 is represented by 75 and so a(14) = 7 + 5 = 12.

Links

Crossrefs

Cf. A000120, A007953, A024655, A053830, A244040.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[7 * Floor[n/9]] + Mod[n, 9]]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\9 * 7) + n % 9); \\ Amiram Eldar, Aug 02 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(9,7,w) for w in [0..200]]

Formula

a(n) = A007953(A024655(n)).

A245354 Sum of digits of n in fractional base 9/5.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 5, 6, 7, 8, 9, 10, 11, 12, 13, 6, 7, 8, 9, 10, 11, 12, 13, 14, 11, 12, 13, 14, 15, 16, 17, 18, 19, 8, 9, 10, 11, 12, 13, 14, 15, 16, 13, 14, 15, 16, 17, 18, 19, 20, 21, 14, 15, 16, 17, 18, 19, 20, 21, 22, 19, 20, 21, 22, 23
Offset: 0

Views

Author

James Van Alstine, Jul 18 2014

Keywords

Comments

The base 9/5 expansion is unique, and thus the sum of digits function is well-defined.

Examples

			In base 9/5 the number 11 is represented by 52 and so a(11) = 5 + 2 = 7.

Links

Crossrefs

Cf. A007953, A024653, A053830.

Programs

  • Mathematica
    a[n_] := a[n] = If[n == 0, 0, a[4 * Floor[n/9]] + Mod[n, 9]]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2025 *)
  • PARI
    a(n) = if(n == 0, 0, a(n\9 * 4) + n % 9); \\ Amiram Eldar, Aug 02 2025
  • Sage
    # uses [basepqsum from A245355]
[basepqsum(9,5,y) for y in [0..200]]

Formula

a(n) = A007953(A024653(n)). - Amiram Eldar, Aug 02 2025
Previous Showing 11-19 of 19 results.

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