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.

A059835 Form triangle as follows: start with three single digits: 0, 1, 2. Each succeeding row is a concatenation of the previous three rows.

Original entry on oeis.org

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

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Author

Jason Earls, Feb 25 2001

Keywords

Comments

Trajectory of 0 under the morphism 0 -> 1, 1-> 2, 2 -> 012. - Robert G. Wilson v, May 20 2014
The sequence of row lengths is A000213. - Michael Somos, May 22 2014

Examples

			Triangle begins:
  0
  1
  2
  0 1 2
  1 2 0 1 2
  2 0 1 2 1 2 0 1 2
  ...
		

References

  • C. Pickover, Wonders of Numbers, Oxford University Press, NY, 2001, p. 273.

Crossrefs

Cf. A059832.

Programs

  • Maple
    T:= proc(n) option remember;
          `if`(n<3, n, seq(T(i), i=n-3..n-1))
        end:
    seq(T(n), n=0..10);  # Alois P. Heinz, May 22 2014
  • Mathematica
    NestList[ Flatten[# /. {0 -> {1}, 1 -> {2}, 2 -> {0, 1, 2}}] &, {0}, 8] // Flatten (* Robert G. Wilson v, May 20 2014 *)

Formula

a(n) = A059832(n) - 1. - Sean A. Irvine, Oct 11 2022

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Feb 26 2001