A106049 Silver dragon four-symbol substitution: characteristic polynomial:x^4-2x^3+x^2-4.

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

Offset

0,1

Comments

Entirely new dragon that tiles with self-similar voids: Level 16 to see it: bb = aa /. 1 -> {1, 0} /. 2 -> {0, 1} /. 3 -> {-1, 0} /. 4 -> {0, -1}; ListPlot[FoldList[Plus, {0, 0}, bb], PlotRange -> All, PlotJoined -> True, Axes -> False];

Links

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

Formula

1->{2, 1, 2}, 2->{3}, 3->{4, 3, 4}, 4->{1}

Mathematica

s[1] = {2, 1, 2}; s[2] = {3}; s[3] = {4, 3, 4}; s[4] = {1}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]] aa = p[7]

Crossrefs

Sequence in context: A058290 A356033 A002285 * A367914 A238234 A367439

Adjacent sequences: A106046 A106047 A106048 * A106050 A106051 A106052

Keyword

nonn,uned

Author

Roger L. Bagula, May 06 2005

Status

approved