I do not dispute the vast majority of your very carefully worded and well-thought-out reply. My use of the word predict in a mathematical context was probably confusing, and I apologize for that. And, you're very close in your restatement of my assertion; indeed, you're close enough for government work.

However, I do take issue with much of your last paragraph. I will respond in parts.

Also, you explicitly mentioned prime numbers generators, that is, implicitly, primality tests. But there are now relatively fast primality tests.

The fact that they are fast is irrelevant. Deeper Blue beat Kasparov, but no-one is going to say that Deeper Blue actually understands the game of chess or the patterns inherent within it. DB used some serious brute force algorithms, even within the heuristics it used to prune the minimax tree. Granted, the game of chess among humans has become somewhat brute-forcish, given that some lines of the Spanish Torture are known for 30 moves (some games of chess don't last 30 moves!). But, there is still an element of analysis within the playing of chess among humans. There is still the attempt to apply patterns to discard 90% of the move options, something computers have not been able to do. If you want a better example, look at the problems with a Go program.

And your claim that "if there was, then current cryptography methods wouldn't work" is plainly false, for those cryptography methods are based on the related but different problem of factorization.

Really? If there was a way to calculate in O(1) time the next prime number larger than a given N (which is, essentially, what the OP was asking for), then cryptography that is based on large number factorization is no longer secure. Think about it for a second - it's not that there is a function P(x) that gives you the next prime number, but the work that leads up to it and that will be based on it. We can go into greater detail offline, if you want. And, factoring large numbers isn't NP-complete or even NP-hard. It's just "NP-slow", in the same way that beating a human in chess (and soon, Go) is NP-slow. The algorithms probably aren't going to improve much, but the computing speed will such that the algorithmic inefficiency factor goes to zero.

Which, in an related side-topic, is why quantum cryptography is such an important leap - it's a completely unrelated way of encrypting data, away from factorizations, primes, and the like. It's physical encryption, not mathematical encryption.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.


In reply to Re^9: a close prime number by dragonchild
in thread a close prime number by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.