Re: FactorInteger

• To: mathgroup at smc.vnet.net
• Subject: [mg14439] Re: FactorInteger
• From: graciark at ippt.gov.pl (Adam Ciarkowski)
• Date: Wed, 21 Oct 1998 03:32:35 -0400
• Organization: IPPT PAN
• References: <70dd3k\$230@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```In article <70dd3k\$230 at smc.vnet.net>, awhopper at hermes.net.au says...
>
>Dear Math Group,
>
>Concerning the Prime Factors of composite integers ;
>
>e.g;
>
>In[1] := 2^4 3^3 4^2
>
>Out[2] = 6912
>
>In[3] := FactorInteger[%]
>
>Out[4] = {{2,4},{3,3},{4,2}}
>
>In Mathematica 3.0 is there anyway the output of FactorInteger can be
>modified to produce the unevaluated prime factors in the usual
>exponential form ?
>
>regards,
>
>Alan Hopper
>Katoomba, Australia
>awhopper at hermes.net.au
>
Try this:
In[1]:=
facInteger[x_]:=Module[{t}, t=FactorInteger[x]; Apply[Times,
Table[HoldForm[#1^#2]&[Apply[Sequence, t[[i]]]], {i, Length[t]}]]]

For example:
In[2]:=facInteger[600]
Out[2]= 2^3 3^1 5^2
In[3]:={%[[3]],    %[[3]] // ReleaseHold} Out[3]= {5^2, 25}