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A077083
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Length of iteration until fixed point is reached when Phi[Sigma[n]+phi(n)]=A077080 is iterated with initial value of n.
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2
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1, 1, 2, 2, 3, 1, 2, 16, 16, 1, 2, 16, 17, 17, 16, 15, 16, 15, 16, 1, 2, 1, 2, 14, 14, 16, 15, 14, 15, 14, 15, 13, 14, 15, 15, 10, 11, 15, 14, 13, 14, 11, 12, 2, 14, 1, 2, 1, 12, 6, 2, 12, 13, 3, 2, 2, 3, 1, 2, 11, 12, 11, 2, 11, 14, 10, 11, 13, 2, 2, 3, 5, 6, 14, 10, 10, 2, 12, 13, 9
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OFFSET
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1,3
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LINKS
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FORMULA
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a(n)=Length[FixedPointList[A077080, n]]-1.
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EXAMPLE
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n=1,2,6,10,..864: a[n]=1, n is fixed point for some n; n=225: results in iteration sequence of 44 terms: {225,522,444,...,471744,653312,570240}, 44=a[225].
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MATHEMATICA
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f[x_] := EulerPhi[DivisorSigma[1, x]+EulerPhi[x]] Table[Length[FixedPointList[f, w]]-1, {w, 1, 1024}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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