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.

A309698 Digits of the 4-adic integer 3^(1/3).

Original entry on oeis.org

3, 2, 3, 1, 1, 0, 3, 3, 1, 0, 2, 0, 3, 3, 0, 3, 1, 3, 0, 1, 1, 3, 0, 3, 3, 3, 3, 3, 1, 0, 3, 2, 0, 2, 0, 0, 1, 2, 3, 2, 0, 3, 1, 0, 1, 1, 1, 2, 1, 2, 0, 1, 0, 1, 3, 2, 2, 1, 1, 1, 3, 2, 2, 0, 3, 3, 3, 0, 3, 0, 0, 0, 3, 0, 2, 3, 3, 0, 3, 2, 1, 2, 1, 2, 2, 1, 0, 0, 0, 2, 0, 1, 3, 0
Offset: 0

Views

Author

Seiichi Manyama, Aug 13 2019

Keywords

Crossrefs

Digits of the k-adic integer (k-1)^(1/(k-1)): this sequence (k=4), A309699 (k=6), A309700 (k=8), A225458 (k=10).

Programs

  • PARI
    N=100; Vecrev(digits(lift((3+O(2^(2*N)))^(1/3)), 4), N)
    
  • Ruby
    def A309698(n)
      ary = [3]
      a = 3
      n.times{|i|
        b = (a + a ** 3 - 3) % (4 ** (i + 2))
        ary << (b - a) / (4 ** (i + 1))
        a = b
      }
      ary
    end
    p A309698(100)

Formula

Define the sequence {b(n)} by the recurrence b(0) = 0 and b(1) = 3, b(n) = b(n-1) + b(n-1)^3 - 3 mod 4^n for n > 1, then a(n) = (b(n+1) - b(n))/4^n.

A309699 Digits of the 6-adic integer 5^(1/5).

Original entry on oeis.org

5, 4, 0, 3, 1, 5, 0, 0, 3, 3, 2, 1, 3, 0, 0, 3, 4, 3, 1, 1, 1, 1, 1, 4, 3, 4, 0, 5, 3, 1, 1, 5, 3, 3, 0, 2, 2, 2, 5, 3, 5, 5, 2, 5, 2, 2, 2, 3, 4, 2, 0, 5, 4, 3, 3, 2, 0, 0, 4, 1, 1, 5, 5, 5, 0, 0, 1, 4, 3, 5, 4, 5, 1, 5, 5, 0, 5, 4, 0, 4, 4, 4, 4, 3, 4, 4, 0, 4, 3, 4, 0, 5, 4, 4
Offset: 0

Views

Author

Seiichi Manyama, Aug 13 2019

Keywords

Comments

x = ...513045,
x^2 = ...433521,
x^3 = ...051525,
x^4 = ...354241,
x^5 = ...000005.

Crossrefs

Digits of the k-adic integer (k-1)^(1/(k-1)): A309698 (k=4), this sequence (k=6), A309700 (k=8), A225458 (k=10).
Cf. A309448.

Programs

  • PARI
    N=100; Vecrev(digits(lift(chinese(Mod((5+O(2^N))^(1/5), 2^N), Mod((5+O(3^N))^(1/5), 3^N))), 6), N)
    
  • Ruby
    def A309699(n)
      ary = [5]
      a = 5
      n.times{|i|
        b = (a + a ** 5 - 5) % (6 ** (i + 2))
        ary << (b - a) / (6 ** (i + 1))
        a = b
      }
      ary
    end
    p A309699(100)

Formula

Define the sequence {b(n)} by the recurrence b(0) = 0 and b(1) = 5, b(n) = b(n-1) + b(n-1)^5 - 5 mod 6^n for n > 1, then a(n) = (b(n+1) - b(n))/6^n.

A309700 Digits of the 8-adic integer 7^(1/7).

Original entry on oeis.org

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

Views

Author

Seiichi Manyama, Aug 13 2019

Keywords

Crossrefs

Digits of the k-adic integer (k-1)^(1/(k-1)): A309698 (k=4), A309699 (k=6), this sequence (k=8), A225458 (k=10).
Cf. A225445.

Programs

  • PARI
    N=100; Vecrev(digits(lift((7+O(2^(3*N)))^(1/7)), 8), N)
    
  • Ruby
    def A309700(n)
      ary = [7]
      a = 7
      n.times{|i|
        b = (a + a ** 7 - 7) % (8 ** (i + 2))
        ary << (b - a) / (8 ** (i + 1))
        a = b
      }
      ary
    end
    p A309700(100)

Formula

Define the sequence {b(n)} by the recurrence b(0) = 0 and b(1) = 7, b(n) = b(n-1) + b(n-1)^7 - 7 mod 8^n for n > 1, then a(n) = (b(n+1) - b(n))/8^n.

A193345 Digits occurring in A173616.

Original entry on oeis.org

1, 1, 7, 8, 7, 0, 1, 9, 7, 2, 3, 0, 8, 5, 5, 1, 9, 6, 5, 4, 6, 3, 8, 8, 0, 5, 5, 0, 3, 2, 7, 9, 6, 8, 6, 7, 5, 0, 4, 9, 5, 0, 5, 9, 9, 0, 5, 2, 5, 3, 3, 6, 6, 3, 4, 8, 2, 7, 8, 0, 0, 9, 0, 9, 4, 8, 5, 0, 3, 4, 4, 4, 8, 7, 2, 2, 9, 7, 9, 3, 7, 7, 7, 3, 8, 4
Offset: 1

Views

Author

Keywords

Comments

a(n) = A173616(n) - 10*A173616(n-1).
This is the 10-adic integer x such that x^9 == (10^n-9) mod 10^n for all n. It is the 10's complement of A225458. - Aswini Vaidyanathan, May 11 2013

Examples

			1111^1111=.........8711; 111^111=........711;
10^(1-4)(8711-711)=8 ==> a(4)=8
Comment from _Aswini Vaidyanathan_, May 11 2013:
1^9 == 1 (mod 10).
11^9 == 91 (mod 100).
711^9 == 991 (mod 1000).
8711^9 == 9991 (mod 10000).
78711^9 == 99991 (mod 100000).
78711^9 == 999991 (mod 1000000).
		

Crossrefs

Programs

  • Mathematica
    repunit[n_] := Sum[10^i, {i,0,n-1}]; a[n_] := 10^(1-n)(PowerMod[repunit[n], repunit[n],10^n] - PowerMod[repunit[n-1], repunit[n-1], 10^(n-1)]); Table[a[n],{n,200}]
  • PARI
    n=0;for(i=1,100,m=(10^i-9);for(x=0,9,if(((n+(x*10^(i-1)))^9)%(10^i)==m,n=n+(x*10^(i-1));print1(x", ");break))) (From Aswini Vaidyanathan, May 11 2013)

Extensions

Edited by N. J. A. Sloane, May 12 2013
Showing 1-4 of 4 results.