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.

A006978 Successive states of the Rule 110 cellular automaton defined by 000, 001, 010, 011, ..., 111 -> 0,1,1,1,0,1,1,0 when started with a single ON cell.

Original entry on oeis.org

1, 3, 7, 13, 31, 49, 115, 215, 509, 775, 1805, 3359, 7985, 12659, 29655, 54909, 130759, 197581, 460383, 855793, 2038675, 3227319, 7562237, 14149127, 33304077, 50625055, 118279729, 220060275, 523730647, 830325757, 1942439431, 3595423245, 8571017759, 12951092785
Offset: 1

Views

Author

Keywords

References

  • Marc LeBrun, personal communication.
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Mathematica
    Map[FromDigits[#, 2] &, CellularAutomaton[110, {{1}, 0}, 30]] (* Ben Branman, Dec 28 2010 *)

Formula

a(n) = A117999(n-1)/2^(n-1). - Pontus von Brömssen, Oct 18 2022

Extensions

More terms from Eric W. Weisstein, Apr 11 2006
Definition clarified by N. J. A. Sloane, Oct 18 2022