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 A106655 Four-symbol substitution, characteristic polynomial: x^4-x^3-1. 0
 4, 3, 2, 1, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 4, 3, 2, 1, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 1, 4, 4, 3, 2, 1, 4, 4, 3, 2, 1, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS This substitution is associated with the Theta(1) Pisot number. Digraph matrix is: {{0, 1, 0, 0}, {0, 0, 1, 0}, {0, 0, 0, 1}, {1, 0, 0, 1}} LINKS FORMULA 1->{2}, 2->{3}, 3->{4}, 5->{1, 4} MATHEMATICA s[1] = {2}; s[2] = {3}; s[3] = {4}; s[4] = {1, 2, 3}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]] aa = p[19] CROSSREFS Sequence in context: A090284 A093580 A196535 * A105313 A085064 A030587 Adjacent sequences:  A106652 A106653 A106654 * A106656 A106657 A106658 KEYWORD nonn,uned AUTHOR Roger L. Bagula, May 12 2005 STATUS approved

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Last modified December 5 20:54 EST 2019. Contains 329779 sequences. (Running on oeis4.)