



0, 2, 5, 11, 16, 7, 37, 149, 7, 27, 11, 11, 23, 2389, 49, 11, 31, 19, 67, 109, 13, 8, 25, 8, 461, 179, 1319, 9, 193, 16, 7, 4931, 121, 7, 9, 8, 7, 8, 2895630887, 25, 19, 13, 19, 41, 2209493509721, 32, 5939, 23, 43, 11
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..50.


EXAMPLE

Fixed point is always a prime or a true power of prime:
a term from A000961.
n=20!=2432902008176640000, a(20)=109 because
fixed point list={2432902008176640000,269439,214,109}}


MATHEMATICA

ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w1], {w, 1, lf[x]}] ep[x_] := Table[Part[ffi[x], 2*w], {w, 1, lf[x]}] sex[x_] := Apply[Plus, ba[x]^ep[x]] Table[FixedPoint[sex, w! ], {w, 1, 128}]


CROSSREFS

Cf. A001414, A056239, A008475, A082081A082084, A000961, A000142.
Sequence in context: A206602 A238159 A080156 * A287558 A024917 A081402
Adjacent sequences: A082080 A082081 A082082 * A082084 A082085 A082086


KEYWORD

nonn


AUTHOR

Labos Elemer, Apr 08 2003


STATUS

approved



