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A106437
Fixed point of the morphism 1->4, 2->1222, 3->2, 4->3444, applied 4*k times to 4.
0
4, 1, 2, 2, 2, 1, 2, 2, 2, 1, 2, 2, 2, 1, 2, 2, 2, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 1, 2, 2, 2, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 2, 3, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 4, 1, 2, 2, 2, 2, 3
OFFSET
0,1
FORMULA
1->{4}, 2->{1, 2, 2, 2}, 3->{2}, 4->{3, 4, 4, 4}.
MATHEMATICA
s[1] = {4}; s[2] = {1, 2, 2, 2}; s[3] = {2}; s[4] = {3, 4, 4, 4}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]] aa = p[5]
CROSSREFS
Sequence in context: A112621 A081448 A322906 * A279605 A054713 A371853
KEYWORD
nonn,easy,less
AUTHOR
Roger L. Bagula, May 29 2005
EXTENSIONS
New name from Joerg Arndt, Nov 07 2016
STATUS
approved