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Re: The prime factors of n.


How about this:

FactorIntegerToList[n_Integer] :=
  Flatten[Table [First[#], Rest[#] // Evaluate] & /@ FactorInteger[n]]

    -- Avraham Shinnar

"Robert G. Wilson v" <rgwv at kspaint.com> wrote in message
news:a3qqjj$27t$1 at smc.vnet.net...
> Hello all,
>
>         I wish to receive a list of prime factors of n not in the form
> returned by FactorInteger. Instead I want only the primes the number of
> times they appear. As an example I will use 72. FactorInteger[72] gives
> { {2,3}, {3,2} }. I wish the list would read { 2, 2, 2, 3, 3 }. Is the
> following the best that I can do? f[n_Integer] := Module[{a =
> FactorInteger[n], b = {}}, While[Length[a] > 0, Do[b = Append[b, a[[1,
> 1]]], {a[[1, 2]]}]; a = Drop[a, 1]]; b] .
>
> See
>
http://www.research.att.com/cgi-bin/access.cgi/as/njas/sequences/eisA.cgi?An
um=037276
>
> Sincerely yours,
>
> Robert G. "Bob" Wilson, V
>
>




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