       Re: count zeros in a number

• To: mathgroup at smc.vnet.net
• Subject: [mg121817] Re: count zeros in a number
• From: "Harvey P. Dale" <hpd1 at nyu.edu>
• Date: Mon, 3 Oct 2011 04:24:18 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201110020636.CAA28027@smc.vnet.net>

```=09
zeroes[n_]:=Module[{idn=IntegerDigits[n]},If[Last[idn]==0,Length[Split[i
dn][[-1]]],0]]
zeroes[24^24 55^55]

Best,

Harvey

-----Original Message-----
From: dimitris [mailto:dimmechan at yahoo.com]
Sent: Sunday, October 02, 2011 2:37 AM
To: mathgroup at smc.vnet.net
Subject: [mg121817] count zeros in a number

Hello.

Consider e.g. the number 24^24*55^55.
This number ends with exactly 55 zeros as the following demonstrate

In:= Mod[24^24*55^55, 10^55]
Mod[24^24*55^55, 10^56]

Out= 0
Out= 20000000000000000000000000000000000000000000000000000000

What I want now is a way to count the zeros that a number ends without
knowing in advance this number of zeros like in the above example.