Re: Re: Automatic expansion of Log[a^n] for a,n explicit positive integers?

*To*: mathgroup at smc.vnet.net*Subject*: [mg28236] Re: [mg28229] Re: [mg28180] Automatic expansion of Log[a^n] for a,n explicit positive integers?*From*: Harald Anlauf <anlauf at hep.tu-darmstadt.de>*Date*: Fri, 6 Apr 2001 01:52:46 -0400 (EDT)*References*: <Pine.LNX.4.30.0104051009080.3276-100000@carmen.nikhef.nl>*Sender*: owner-wri-mathgroup at wolfram.com

Hi, thanks for your suggestions and help! I also received a very clever and general solution by Erich Mueller <emuelle1 at uiuc.edu>: <quote> How about implementing the rule using pattern substitution, like this: Log[12] + Log[x] /. Log[a_Integer] :> Plus @@ (#2Log[#1] & @@ # & /@ FactorInteger[a]) Which returns 2 Log[2] + Log[3] + Log[x] </quote> Mianlai's solution has its own advantages, as no explicit substitution is required. I may reconsider it when needed. Again, many thanks for your answers. Regards, -Harald