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A097576
A 2 X 2 matrix version of A005185: Hofstadter's sequence.
0
0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 3, 3, 3, 6, 3, 3, 3, 6, 4, 4, 4, 8, 5, 5, 5, 10, 5, 5, 5, 10, 6, 6, 6, 12, 6, 6, 6, 12, 6, 6, 6, 12, 8, 8, 8, 16, 8, 8, 8, 16, 8, 8, 8, 16, 10, 10, 10, 20, 9, 9, 9, 18, 10, 10, 10, 20, 11, 11, 11, 22, 11, 11, 11, 22, 12, 12, 12, 24, 12, 12, 12, 24, 12, 12, 12
OFFSET
0,8
FORMULA
A[n_]:=A[n]=A[n-A[n-1][[1, 1]]]+A[n-A[n-2][[1, 2]]]; A[0]:={{0, 1}, {1, 1}}; A[1]:={{1, 1}, {1, 2}};
MATHEMATICA
Clear[A, M] (* Hofstadter 2 X 2 Matrix sequence*) (* by Roger L. Bagula *) digits=100 A[n_]:=A[n]=A[n-A[n-1][[1, 1]]]+A[n-A[n-2][[1, 2]]]; A[0]:={{0, 1}, {1, 1}}; A[1]:={{1, 1}, {1, 2}}; (* flattened sequence of 2 X 2 matrices made with a Hofstadter recurrence*) b=Flatten[Table[A[n], {n, 0, digits}]] ListPlot[b, PlotJoined->True]
CROSSREFS
Cf. A005185.
Sequence in context: A023153 A023159 A098983 * A029250 A341584 A110884
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Aug 28 2004
STATUS
approved