Re: Factoring large composite numbers



"SplinterCell" <suren.srikanthan@xxxxxxxxx> writes:

Let us take an integer which we wish to factor: x.
Now let y = the smallest factor greater than x, where y - x is a square
number.
Let y - x = z
Then, x = (sqrt(y) - sqrt(z))(sqrt(y) + sqrt(z))

You mean y is the smallest square larger than x such that...
a) HOw do you find y such that y-x is a square? -- There are very very very
many squares larger than x and most of them are not of the form such that
y-x is a square as well.

b) Your observation forms the basis of the method of a poster here called Stevens who
keeps posting that he has solved the factoring problem. So far he has not
managed to factor any large numbers, despite claiming to have
revolutionised the subject.
Ie, the observation is a very old one. Unfortunately noone has managed to
find a way to use it to make factoring any easier. ( Well, if you happen to
choose your number so that it is one less than some square, then of course
this method says it is very weak.)


For example:

Let x = 15
Let y = 16
y - x = 1 = z
sqrt(z) = +1 or -1
x = (4 - 1)(4 + 1)
= 3 * 5


Does this hold much promise or is this a dead end?

Please be aware that I am only 15 years old, but I am extremely
interested in cryptography and factorising large numbers.


The subject is centuries old. Ie, the easy methods have been tried. It is
suspected that no polynomial time algorithm exists (ie it is NP-P) but no
proof of that exists (Not least because no proof that NP-P is non-null
exists)

.



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