A105258 Triangle of trajectory of 1 under the morphism 1->2, 2->13, 3->1.

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

Offset

0,3

Links

Table of n, a(n) for n=0..104.

Index entries for sequences that are fixed points of mappings

Example

The first steps are:
{1}
{1, 2}
{1, 2, 2, 1, 3}
{1, 2, 2, 1, 3, 2, 1, 3, 1, 3, 2, 1}

Mathematica

s[1] = {2}; s[2] = {1, 3}; s[3] = {1}; t[a_] := Join[a, Flatten[s /@ a]]; p[0] = {1}; p[1] = t[{1}]; p[n_] := t[p[n - 1]] aa = Flatten[Table[p[n], {n, 0, 6}]]

Prog

(PARI) {a(n)=local(m, v, w); v=w=[1]; while(length(w)<n, m=length(v); for(k=1, m, v=concat(v, [[2], [1, 3], [1]][v[k]])); w=concat(w, v)); w[n]}

Crossrefs

Cf. A073058, A105111.

Sequence in context: A350560 A050362 A095686 * A329173 A366493 A378776

Adjacent sequences: A105255 A105256 A105257 * A105259 A105260 A105261

Keyword

nonn,tabf

Author

Roger L. Bagula, Apr 14 2005

Extensions

Edited by the Associate Editors of the OEIS, Apr 07 2009

Status

approved