

A317952


Trajectory of 1 under repeated application of the morphism 1>121, 2>232, 3>343, 4>414.


1



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

0,2


LINKS

Robert Israel, Table of n, a(n) for n = 0..10000
Julien Cassaigne, Juhani Karhumäki, Svetlana Puzynina, On kabelian palindromes, Information and Computation, Volume 260, June 2018, Pages 8998. See Lemma 1.


FORMULA

From Robert Israel, Aug 20 2018: (Start)
a(3*k) = a(3*k+2) = a(k).
a(3*k+1) == 1 + a(k) mod 4. (End)


MAPLE

A:= [1]:
for k from 1 to 5 do A:= subs([1=(1, 2, 1), 2=(2, 3, 2), 3=(3, 4, 3), 4=(4, 1, 4)], A);
od:
op(A); # Robert Israel, Aug 20 2018


MATHEMATICA

SubstitutionSystem[{1 > {1, 2, 1}, 2 > {2, 3, 2}, 3 > {3, 4, 3}, 4 > {4, 1, 4}}, 1, 5] // Last (* JeanFrançois Alcover, Apr 06 2020 *)


CROSSREFS

Sequence in context: A286281 A229830 A105203 * A059131 A059129 A349954
Adjacent sequences: A317949 A317950 A317951 * A317953 A317954 A317955


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Aug 20 2018


STATUS

approved



