Re: primality

Antony Clements wrote:
"Ertugrul Soeylemez" <do-not-spam-me@xxxxxxxx> wrote in message news:f02ko7$3oc$00$1@xxxxxxxxxxxxxxxxxxxx

Okay, then I misunderstood you. But what is the point in doing this?

the point is that it is easier and faster to use an algorithm to generate a prime/semiprime/compound number that happens to be odd rather than generating the number randomly and testing for primality because if the primality test fails then a new random number has to be generated and tested. but using an algorithm will produce inear results once the initial state is known.

You just grab any random number that's about the size you need and set the first and last bit to "1" (the first bit makes it the size you need and the last bit makes it an odd number - it is very simple and very quick.


I don't know which dictionary you're using, but `code' and `ciphertext'
is not the same. Ciphertext is plaintext transformed in such a way that
a key is needed to undo the transformation. That ciphertext is stored
in a particular representation. This representation is called the code.

Different things can be encoded using different codes. Examples of
codes: Finite data as base N numbers (decimal, hexadecimal, Base64...)
vs. UUEncode, colors in RGB vs. HSV, text as UTF-8 vs. Latin-1, etc.

i stand corrected, thank you.


.

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