A103684 Triangle read by rows, based on the morphism f: 1->{1,2}, 2->{1,3}, 3->{1}. First row is 1. If current row is a,b,c,..., then the next row is a,b,c,...,f(a),f(b),f(c),...

1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 3, 1, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 1, 2, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 1, 2, 1, 3, 1, 2, 1, 3, 1, 2, 1, 1, 2, 1, 3, 1, 2, 1, 1, 2, 1, 3, 1

Offset: 1

Author

Roger L. Bagula, Mar 26 2005

Keywords

• nonn
• tabf

Examples

			[1], [1,1,2], [1,1,2,1,2,1,2,1,3], [1,1,2,1,2,1,2,1,3,1,2,1,2,1,3,1,2,1,3,1,2,1,3,1,2,1], ...
		

Links

• G. C. Greubel, Table of n, a(n) for the first 8 rows, flattened

Crossrefs

Cf. A073058, A103685, A103682.

Programs

Mathematica

NestList[ Flatten[ Join[ #, # /. {1 -> {1, 2}, 2 -> {1, 3}, 3->{1}}]] &, {1}, 4] // Flatten (* Robert G. Wilson v, Jul 09 2006 - corrected by G. C. Greubel, Oct 26 2017 *)

PARI

{a(n)=local(m,v,w); v=w=[1]; while(length(w)Michael Somos, Apr 16 2005 */

Extensions

Image of {3} in the definition corrected by R. J. Mathar, Nov 18 2010