



0, 2, 5, 5, 5, 19, 5, 7, 7, 11, 13, 13, 23, 13, 19, 101, 61, 5, 19, 5, 11, 5, 5, 7, 23, 7, 5, 7, 283, 293, 5, 5, 7, 367, 379, 389, 23, 7, 463, 5, 13, 11, 29, 5, 23, 7, 7, 19, 5, 5, 5, 5, 61, 7, 73, 47, 857, 7, 947, 5, 29, 7, 13, 5, 5, 19, 137, 7, 5, 7, 11, 23, 353, 53, 11, 1471, 1489
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..77.


EXAMPLE

Fixed point seems to be always a prime:tested for 1<n<201
n=20!=2432902008176640000: a(20)=5 with fixedpointlist=
{2432902008176640000,154,20,9,6,5,5}


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]}] slog[x_] := Apply[Plus, ba[x]*ep[x]] Table[FixedPoint[slog, w! ], {w, 1, 128}]


CROSSREFS

Cf. A001414, A056239, A008475, A082081A082083, A000961, A000142.
Sequence in context: A256302 A205396 A082086 * A094236 A205444 A270705
Adjacent sequences: A082081 A082082 A082083 * A082085 A082086 A082087


KEYWORD

nonn


AUTHOR

Labos Elemer, Apr 08 2003


STATUS

approved



