PrimeQ[Floor[Pi*10^i]]
- To: mathgroup at smc.vnet.net
- Subject: [mg15257] PrimeQ[Floor[Pi*10^i]]
- From: haha at astral.magic.ca (Hans Havermann)
- Date: Wed, 30 Dec 1998 01:50:20 -0500
- Organization: Rarebit Dreams
- Sender: owner-wri-mathgroup at wolfram.com
<<Utilities`ShowTime`
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,0,999}]],True]] 268.233
Second
{1,2,6,38}
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,1000,1999}]],True]+1000]
2961.12 Second
{}
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,2000,2999}]],True]+2000]
13656.6 Second
{}
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,3000,3999}]],True]+3000]
40945.8 Second
{}
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,4000,4999}]],True]+4000]
65517.3 Second
{}
Flatten[Position[PrimeQ[Table[Floor[Pi*10^i],{i,5000,5999}]],True]+5000]
109428. Second
{}
Well, I'm getting to a point where I'm interested in doing the same -
further, only faster. I tried a 10000-place approximation to Pi instead
of Pi but my time-saving seemed minimal. Any ideas?