Re: Binary System Problem
- To: mathgroup at smc.vnet.net
- Subject: [mg18689] Re: Binary System Problem
- From: "Ugo Marchesini" <vi13818 at iperbole.bologna.it>
- Date: Thu, 15 Jul 1999 01:46:05 -0400
- Organization: NETTuno
- References: <7mek54$9it@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Frieder Schweigert ha scritto nel messaggio <7mek54$9it at smc.vnet.net>...
>Hi,
>
>does anybody know an algorithm or generating system for
>those binary numbers with a fix amount of '1's,
>for example (four times '1'):
>
> 1111
>10111
>11011
>11101
>11110
>.
>.
>..
>
>
>Greetings Frieder.
>
I hope this is the algoritm that you are looking for
alg[in_]:=Module[{},p1=Sum[2^i,{i,0,in-1}];
p2=IntegerDigits[p1,2];
p3=Table[p2,{i,1,in}];
For[i=1,i<in+1,i++,p3[[i,i]]=0];
MatrixForm[p3]
]
alg[7]
0 1 1 1 1 1 1
1 0 1 1 1 1 1
1 1 0 1 1 1 1
1 1 1 0 1 1 1
1 1 1 1 0 1 1
1 1 1 1 1 0 1
1 1 1 1 1 1 0