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Program to find Primes of the form prime(n+2) * prime(n+1) - prime(n) +- 1.


On Wed, 03 Oct 2018 09:43:07 -0700, Musatov wrote:

> On Wednesday, October 3, 2018 at 11:12:43 AM UTC-5, Michael Torrie
> wrote:
>> On 10/03/2018 09:26 AM, Musatov wrote:
>> > I don't even know where to begin! (I'm reading the Dummies book)
>> 
>> If you have no experience in computer programming, it's going to be a
>> steep learning curve.
>> 
>> But your first step is to learn Python and how to write programs in it.
>> That book and others will help with that.  You'll have to write lots of
>> simple programs unrelated to primes along the way that help you
>> understand programming concepts.
>> 
>> If you already have experience in other languages, the task will be
>> easier.
>> 
>> Computer programming is quite natural to some (small children seem to
>> get it much easier than us adults), but I've seen others struggle to
>> grasp the abstract concepts for years.
>> 
>> Once you've grasped basic Python programming, you can return top the
>> original problem at hand.  Start by identifying the process or
>> algorithm that would find these primes. In other words, how would you
>> do it on pen and paper?  Computer programs are not magic.  They are
>> only expressions of human thinking. Often some very smart
>> mathematicians have come up with powerful algorithms (a step-by-step
>> process) to do these things,
>> and your job as a programmer is to turn this mathematical process into
>> a computer program using things like loops and Boolean logic. How would
>> you find these primes using your pen, paper, and calculator?
> 
> Literally, how I found them was taking a list of primes and checking if
> the calculations with the lesser primes resulted in numbers also further
> along on the list.
> 
> Another way I guess would be to do the calculations then check if the
> number is prime.

That is exactly how you do it with in a program.

create a loop & check to see if the target number can be divided by each 
possible divisor in turn
.
for large numbers this will take a large number of tests (hey that is why 
you have the computer do them, it is faster than you & does not get 
bored ;-) ) there are numerous tricks for speeding up this process once 
you have the basic working.

start by testing small numbers & then use your real data once you have 
something that works

as a starter a simple loop in python could be as follows

for x in xrange(10):
	print x

once you have an outline of a program post it back here if things dont 
work as expected



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