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Re: Inverse of a Number

• Subject: [mg2570] Re: Inverse of a Number
• From: wagner at bullwinkle.cs.Colorado.EDU (Dave Wagner)
• Date: Tue, 21 Nov 1995 09:25:10 -0500
• Approved: usenet@wri.com
• Distribution: local
• Newsgroups: wri.mathgroup
• Organization: University of Colorado, Boulder

In article <DI9Ay8.Gz at wri.com>, Enrico C. Walker <ewalke1 at gl.umbc.edu> wrote:
>First of all, I thank you all those who responded to my earlier question.
>My second question is How to find the inverse of a number in some Modulo 
>system. 

(Local) In[1]:= ?PowerMod
PowerMod[a, b, n] gives Mod[a^b, n]. For negative b,
   PowerMod[a, b, n] gives modular inverses.

(Local) In[3]:= PowerMod[9, -1, 26]
(Local) Out[3]= 3


		Dave Wagner
		Principia Consulting
		(303) 786-8371
		dbwagner at princon.com
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