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 11-14 of 14 results.

A081775 Continued fraction for sum(k>=0,1/7^(2^k-1)).

Original entry on oeis.org

1, 6, 1, 6, 7, 6, 1, 6, 6, 1, 6, 6, 1, 5, 1, 6, 6, 1, 6, 7, 6, 1, 6, 6, 1, 5, 1, 6, 7, 6, 1, 6, 6, 1, 5, 1, 6, 6, 1, 6, 6, 1, 6, 7, 6, 1, 6, 6, 1, 5, 1, 6, 7, 6, 1, 6, 6, 1, 6, 6, 1, 5, 1, 6, 6, 1, 6, 7, 6, 1, 5, 1, 6, 6, 1, 6, 7, 6, 1, 6, 6, 1, 5, 1, 6, 6, 1, 6, 6, 1, 6, 7, 6, 1, 6, 6, 1, 5, 1, 6, 7, 6, 1, 6, 6
Offset: 1

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Author

Benoit Cloitre, Apr 10 2003

Keywords

Comments

Contains only elements 1<=a(n)<=7 ( but 2,3 and 4 never occur)

Crossrefs

Cf. A004200.

A081776 Continued fraction for sum(k>=0,1/8^(2^k-1)).

Original entry on oeis.org

1, 7, 1, 7, 8, 7, 1, 7, 7, 1, 7, 7, 1, 6, 1, 7, 7, 1, 7, 8, 7, 1, 7, 7, 1, 6, 1, 7, 8, 7, 1, 7, 7, 1, 6, 1, 7, 7, 1, 7, 7, 1, 7, 8, 7, 1, 7, 7, 1, 6, 1, 7, 8, 7, 1, 7, 7, 1, 7, 7, 1, 6, 1, 7, 7, 1, 7, 8, 7, 1, 6, 1, 7, 7, 1, 7, 8, 7, 1, 7, 7, 1, 6, 1, 7, 7, 1, 7, 7, 1, 7, 8, 7, 1, 7, 7, 1, 6, 1, 7, 8, 7, 1, 7, 7
Offset: 1

Views

Author

Benoit Cloitre, Apr 10 2003

Keywords

Comments

Contains only elements 1<=a(n)<=8 ( but 2,3,4 and 5 never occur)

Crossrefs

Cf. A004200.

A081777 Continued fraction for sum(k>=0,1/9^(2^k-1)).

Original entry on oeis.org

1, 8, 1, 8, 9, 8, 1, 8, 8, 1, 8, 8, 1, 7, 1, 8, 8, 1, 8, 9, 8, 1, 8, 8, 1, 7, 1, 8, 9, 8, 1, 8, 8, 1, 7, 1, 8, 8, 1, 8, 8, 1, 8, 9, 8, 1, 8, 8, 1, 7, 1, 8, 9, 8, 1, 8, 8, 1, 8, 8, 1, 7, 1, 8, 8, 1, 8, 9, 8, 1, 7, 1, 8, 8, 1, 8, 9, 8, 1, 8, 8, 1, 7, 1, 8, 8, 1, 8, 8, 1, 8, 9, 8, 1, 8, 8, 1, 7, 1, 8, 9, 8, 1, 8, 8
Offset: 1

Views

Author

Benoit Cloitre, Apr 10 2003

Keywords

Comments

Contains only elements 1<=a(n)<=9 ( but 2,3,4,5 and 6 never occur)

Crossrefs

Cf. A004200.

A283874 The Pierce expansion of the number Sum_{k>=1} 1/3^((2^k) - 1).

Original entry on oeis.org

2, 3, 4, 9, 10, 81, 82, 6561, 6562, 43046721, 43046722, 1853020188851841, 1853020188851842, 3433683820292512484657849089281, 3433683820292512484657849089282, 11790184577738583171520872861412518665678211592275841109096961, 11790184577738583171520872861412518665678211592275841109096962
Offset: 0

Views

Author

Kutlwano Loeto, Mar 24 2017

Keywords

Comments

This sequence is the Pierce expansion of the number 3*s(3) - 1 = 0.370827687432918983346475478500709113969827799141493576... where s(u) = Sum_{k>=0} 1/u^(2^k) for u=3 has been considered by N. J. A. Sloane in A004200.
The continued fraction expansion of the number 3*s(3)-1 is essentially A081771.

Examples

			The Pierce expansion of 0.3708276874329189833 starts as 1/2 - 1/(2*3) + 1/(2*3*4) - 1/(2*3*4*9) + 1/(2*3*4*9*10) - 1/(2*3*4*9*10*81) + ...
		

Programs

  • Maple
    L:=[2]: for k from 0 to 6 do: L:=[op(L),3^(2^k),3^(2^k)+1]: od: print(L);
  • PARI
    a(n) = if (n==0, 2, if (n%2, 3^(2^((n-1)/2)), 3^(2^((n-2)/2))+1)); \\ Michel Marcus, Mar 31 2017

Formula

a(0) = 2, a(2k+1) = 3^(2^k), a(2k+2) = 3^(2^k) + 1, k >= 0.
Previous Showing 11-14 of 14 results.