23 lines
666 B
Markdown
23 lines
666 B
Markdown
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# How close is too close?
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- if \(\rm\:|p-q| < n^{1/3},\:\)
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- then n can factored in polynomial time using fermat algorithm:
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```python
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def fermatfactor(N):
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if N <= 0: return [N]
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if is_even(N): return [2,N/2]
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a = ceil(sqrt(N))
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while not is_square(a^2-N):
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a = a + 1
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b = sqrt(a^2-N)
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return [a - b,a + b]
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```
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# Instructions
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This folders contains two public keys:
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- `veryclosepq.pem`
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- `notsoclosepq.pem`
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Use the provided algorithm to factor n.
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A detailed explanation of this method can be found [on Daniel's Bernstein website](https://facthacks.cr.yp.to/fermat.html), or [John D. Cooks's](https://www.johndcook.com/blog/2018/10/28/fermat-factoring/).
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