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A096865
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Function A062401[x]=phi[sigma[x]] is iterated. Starting with n, a(n) is the smallest term arising in trajectory, either in transient or in terminal cycle.
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1
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1, 2, 2, 4, 2, 4, 4, 8, 9, 4, 4, 12, 4, 8, 8, 16, 4, 16, 8, 12, 16, 12, 8, 16, 16, 12, 16, 16, 8, 16, 16, 32, 16, 16, 16, 36, 16, 16, 16, 16, 12, 32, 12, 16, 16, 16, 16, 48, 36, 48, 16, 32, 16, 32, 16, 32, 32, 16, 16, 48, 16, 32, 48, 64, 16, 48, 32, 36, 32, 48, 16, 72, 36, 36, 48
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| n=255: list={255,144,360,288,[432,480],432..}, a[255]=144 as a transient term;
n=254: list=254,[128],128,..},a[254]=128, as a fixed point.
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MATHEMATICA
| fs[x_] :=EulerPhi[DivisorSigma[1, x]] itef[x_, hos_] :=NestList[fs, x, hos] Table[Min[itef[w, 20]], {w, 1, 256}]
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CROSSREFS
| Cf. A062401, A062402, A095955, A096859-A096866.
Sequence in context: A054536 A001316 A161831 * A116466 A116467 A079314
Adjacent sequences: A096862 A096863 A096864 * A096866 A096867 A096868
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Jul 21 2004
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