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 1-7 of 7 results.

A319808 a(n) = A319725(n) + A319656(n).

Original entry on oeis.org

0, 2, 4, 6, 8, 10, 12, 14, 9, 18, 27, 36, 45, 54, 63, 72, 18, 27, 36, 45, 54, 63, 72, 81, 27, 36, 45, 54, 63, 72, 81, 90, 36, 45, 54, 63, 72, 81, 90, 99, 45, 54, 63, 72, 81, 90, 99, 108, 54, 63, 72, 81, 90, 99, 108, 117, 63, 72, 81, 90, 99, 108, 117, 126, 65, 81, 146, 211
Offset: 0

Views

Author

Seiichi Manyama, Sep 28 2018

Keywords

Comments

This sequence is different from A055956.

Links

Crossrefs

Base b: A319785 (b=2), A319803 (b=3), A319804 (b=4), A319805 (b=5), A319806 (b=6), A319807 (b=7), this sequence (b=8), A319747 (b=9), A052008 (b=10).
Cf. A055956, A319656, A319725.

Programs

  • Mathematica
    Table[FromDigits[Reverse[#], 8] + FromDigits[#, 8] & [Sort[IntegerDigits[n, 8]]], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
  • PARI
    a(n) = my(nd=digits(n, 8)); fromdigits(vecsort(nd), 8) + fromdigits(vecsort(nd,,4), 8); \\ Michel Marcus, Sep 28 2018

A319722 Write n in 5-ary, sort digits into decreasing order.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 11, 16, 21, 10, 11, 12, 17, 22, 15, 16, 17, 18, 23, 20, 21, 22, 23, 24, 25, 30, 55, 80, 105, 30, 31, 56, 81, 106, 55, 56, 61, 86, 111, 80, 81, 86, 91, 116, 105, 106, 111, 116, 121, 50, 55, 60, 85, 110, 55, 56, 61, 86, 111, 60, 61, 62, 87, 112, 85
Offset: 0

Views

Author

Seiichi Manyama, Sep 26 2018

Keywords

Links

Crossrefs

b-ary: A073138 (b=2), A319651 (b=3), A319720 (b=4), this sequence (b=5), A319723 (b=6), A319724 (b=7), A319725 (b=8), A319726 (b=9), A004186 (b=10).
Cf. A165032, A319653.

Programs

  • Mathematica
    Table[FromDigits[ReverseSort[IntegerDigits[n, 5]], 5], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
  • PARI
    a(n) = fromdigits(vecsort(digits(n, 5), , 4), 5); \\ Michel Marcus, Sep 26 2018
  • Ruby
    def A(k, n)
  (0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(5, 100)

Formula

n <= a(n) < 5n. - Charles R Greathouse IV, Aug 07 2024

A319723 Write n in 6-ary, sort digits into decreasing order.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 13, 19, 25, 31, 12, 13, 14, 20, 26, 32, 18, 19, 20, 21, 27, 33, 24, 25, 26, 27, 28, 34, 30, 31, 32, 33, 34, 35, 36, 42, 78, 114, 150, 186, 42, 43, 79, 115, 151, 187, 78, 79, 85, 121, 157, 193, 114, 115, 121, 127, 163, 199, 150, 151, 157, 163
Offset: 0

Views

Author

Seiichi Manyama, Sep 26 2018

Keywords

Links

Crossrefs

b-ary: A073138 (b=2), A319651 (b=3), A319720 (b=4), A319722 (b=5), this sequence (b=6), A319724 (b=7), A319725 (b=8), A319726 (b=9), A004186 (b=10).
Cf. A165051, A319654.

Programs

  • Mathematica
    Table[FromDigits[ReverseSort[IntegerDigits[n, 6]], 6], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
  • PARI
    a(n) = fromdigits(vecsort(digits(n, 6), , 4), 6); \\ Michel Marcus, Sep 26 2018
  • Ruby
    def A(k, n)
  (0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(6, 100)

Formula

n <= a(n) < 6n. - Charles R Greathouse IV, Aug 07 2024

A319724 Write n in 7-ary, sort digits into decreasing order.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 15, 22, 29, 36, 43, 14, 15, 16, 23, 30, 37, 44, 21, 22, 23, 24, 31, 38, 45, 28, 29, 30, 31, 32, 39, 46, 35, 36, 37, 38, 39, 40, 47, 42, 43, 44, 45, 46, 47, 48, 49, 56, 105, 154, 203, 252, 301, 56, 57, 106, 155, 204, 253, 302, 105, 106, 113, 162
Offset: 0

Views

Author

Seiichi Manyama, Sep 26 2018

Keywords

Links

Crossrefs

b-ary: A073138 (b=2), A319651 (b=3), A319720 (b=4), A319722 (b=5), A319723 (b=6), this sequence (b=7), A319725 (b=8), A319726 (b=9), A004186 (b=10).
Cf. A165071, A319655.

Programs

  • Mathematica
    Table[FromDigits[ReverseSort[IntegerDigits[n, 7]], 7], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
  • PARI
    a(n) = fromdigits(vecsort(digits(n, 7), , 4), 7); \\ Michel Marcus, Sep 26 2018
  • Ruby
    def A(k, n)
  (0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(7, 100)

Formula

n <= a(n) < 7n. - Charles R Greathouse IV, Aug 07 2024

A319726 Write n in 9-ary, sort digits into decreasing order.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 19, 28, 37, 46, 55, 64, 73, 18, 19, 20, 29, 38, 47, 56, 65, 74, 27, 28, 29, 30, 39, 48, 57, 66, 75, 36, 37, 38, 39, 40, 49, 58, 67, 76, 45, 46, 47, 48, 49, 50, 59, 68, 77, 54, 55, 56, 57, 58, 59, 60, 69, 78, 63, 64, 65, 66, 67, 68, 69
Offset: 0

Views

Author

Seiichi Manyama, Sep 26 2018

Keywords

Links

Crossrefs

b-ary: A073138 (b=2), A319651 (b=3), A319720 (b=4), A319722 (b=5), A319723 (b=6), A319724 (b=7), A319725 (b=8), this sequence (b=9), A004186 (b=10).
Cf. A165110, A319657.

Programs

  • Mathematica
    Table[FromDigits[Reverse[Sort[IntegerDigits[n,9]]],9],{n,0,70}] (* Harvey P. Dale, Oct 26 2022 *)
  • PARI
    a(n) = fromdigits(vecsort(digits(n, 9), , 4), 9); \\ Michel Marcus, Sep 26 2018
  • Ruby
    def A(k, n)
  (0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(9, 100)

Formula

n <= a(n) < 9n. - Charles R Greathouse IV, Aug 07 2024

A030107 Base 8 reversal of n (written in base 10).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 1, 9, 17, 25, 33, 41, 49, 57, 2, 10, 18, 26, 34, 42, 50, 58, 3, 11, 19, 27, 35, 43, 51, 59, 4, 12, 20, 28, 36, 44, 52, 60, 5, 13, 21, 29, 37, 45, 53, 61, 6, 14, 22, 30, 38, 46, 54, 62, 7, 15, 23, 31, 39, 47, 55, 63, 1, 65, 129, 193, 257, 321, 385, 449, 9, 73, 137
Offset: 0

Views

Author

David W. Wilson

Keywords

Links

Crossrefs

Cf. A030101 - A030108, A004086, A055956, A319725.

Programs

  • Mathematica
    Table[FromDigits[Reverse[IntegerDigits[n,8]],8],{n,0,80}] (* Harvey P. Dale, Jun 04 2021 *)
  • PARI
    a(n,b=8)=subst(Polrev(base(n,b)),x,b) /* where */
base(n,b)={my(a=[n%b]);while(n\=b,a=concat(n%b,a));a}  \\ M. F. Hasler, Nov 04 2011

A319720 Write n in 4-ary, sort digits into decreasing order.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 9, 13, 8, 9, 10, 14, 12, 13, 14, 15, 16, 20, 36, 52, 20, 21, 37, 53, 36, 37, 41, 57, 52, 53, 57, 61, 32, 36, 40, 56, 36, 37, 41, 57, 40, 41, 42, 58, 56, 57, 58, 62, 48, 52, 56, 60, 52, 53, 57, 61, 56, 57, 58, 62, 60, 61, 62, 63, 64, 80, 144, 208, 80, 84
Offset: 0

Views

Author

Seiichi Manyama, Sep 26 2018

Keywords

Links

Crossrefs

b-ary: A073138 (b=2), A319651 (b=3), this sequence (b=4), A319722 (b=5), A319723 (b=6), A319724 (b=7), A319725 (b=8), A319726 (b=9), A004186 (b=10).
Cf. A165012, A319652.

Programs

  • Mathematica
    Table[FromDigits[ReverseSort[IntegerDigits[n, 4]], 4], {n, 0, 100}] (* Paolo Xausa, Aug 07 2024 *)
  • PARI
    a(n) = fromdigits(vecsort(digits(n, 4), , 4), 4); \\ Michel Marcus, Sep 26 2018
  • Ruby
    def A(k, n)
  (0..n).map{|i| i.to_s(k).split('').sort.reverse.join.to_i(k)}
end
p A(4, 100)

Formula

n <= a(n) < 4n. - Charles R Greathouse IV, Aug 07 2024
Showing 1-7 of 7 results.

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