A106826 Trajectory of 1 under the morphism 1->{2,1}, 2->{2,3}, 3->{4,3}, 4->{4,1}.

2, 3, 4, 3, 4, 1, 4, 3, 4, 1, 2, 1, 4, 1, 4, 3, 4, 1, 2, 1, 2, 3, 2, 1, 4, 1, 2, 1, 4, 1, 4, 3, 4, 1, 2, 1, 2, 3, 2, 1, 2, 3, 4, 3, 2, 3, 2, 1, 4, 1, 2, 1, 2, 3, 2, 1, 4, 1, 2, 1, 4, 1, 4, 3, 4, 1, 2, 1, 2, 3, 2, 1, 2, 3, 4, 3, 2, 3, 2, 1, 2, 3, 4, 3, 4, 1, 4, 3, 2, 3, 4, 3, 2, 3, 2, 1, 4, 1, 2, 1, 2, 3, 2, 1, 2

Offset

0,1

Comments

This is the reverse of the morphism in A105500 and the trajectory of 1 actually starts with 2 instead of 1.

Links

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

F. M. Dekking, Recurrent sets, Advances in Mathematics, vol. 44, no. 1 (1982), 78-104.

Index entries for sequences that are fixed points of mappings

Mathematica

Nest[ Flatten[ # /. {1 -> {2, 1}, 2 -> {2, 3}, 3 -> {4, 3}, 4 -> {4, 1}}] &, {1}, 8] (*Robert G. Wilson v, Jun 20 2005 *)

Prog

(PARI) {a(n)=local(A); if(n<0, 0, n++; A=[2]; while(length(A)<n, A=concat(vector(length(A), k, [[2, 1], [2, 3], [4, 3], [4, 1]][A[k]]))); A[n])}

Crossrefs

Cf. A105500.

Sequence in context: A328314 A286245 A279849 * A259582 A139048 A182101

Adjacent sequences: A106823 A106824 A106825 * A106827 A106828 A106829

Keyword

nonn,easy

Author

N. J. A. Sloane, May 20 2005

Status

approved