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9 votes
3 answers
9k views

Algorithm for detecting prime powers

While reading Peter Shor's paper Polynomial-Time Algorithms for Prime Factorization and Discrete Logarithms on a Quantum Computer, I came across the following quote: "This scheme will thus work as ...
Xander Faber's user avatar
  • 1,199
8 votes
2 answers
749 views

Factoring some integer in the given interval

I'm posting this question here (rather than on CSTheory) since it seems to require much more knowledge about number theory than algorithms. Let N be a positive integer. Is there an efficient (i.e. ...
Sadeq Dousti's user avatar
2 votes
1 answer
132 views

On an integer factoring algorithm based on smooth class number of quadratic fields

We got an algorithm and toy implementation of integer factoring algorithm based on smooth class number of quadratic fields. It is close to the elliptic curve factorization method (ECM) and succeeds if ...
joro's user avatar
  • 25.4k
2 votes
3 answers
1k views

Finding integer representation as difference of two triangular numbers

Since $n = \frac{n(n+1)}{2}-\frac{n(n-1)}{2}$, every natural number can be represented as the difference of two triangular numbers: $ n = \frac{a(a+1)}{2}-\frac{b(b-1)}{2}$. Finding such a ...
user avatar
2 votes
1 answer
134 views

On a efficient algorithm for factoring bivariate polynomials modulo composite modulus assuming the solution is unique

We found and implemented in sage efficient algorithm for factoring bivariate polynomials modulo composite modulus assuming the solution is unique up to a constant factor. More formally let $K=\mathbb{...
joro's user avatar
  • 25.4k
2 votes
1 answer
264 views

Does Coppersmith's method always finds non-trivial factor of integers of the form $n=a(2^k b+1)$ assuming $1 < a<2^k b +1$ and $b < n^{1/4-0.05}$?

Got an argument and numeric evidence that pari's implementation of Coppersmith's method finds non trivial factor of integers of certain form under some assumptions very efficiently. Three $5000$ bit ...
joro's user avatar
  • 25.4k
2 votes
0 answers
187 views

Factoring integers of the form $n=p q^2$ using elliptic curves

We got argument and strong experimental support that integers of the form $n=p q^2$ can be factored using elliptic curves easier than general integers Q1 Is this known? Added This is known since at ...
joro's user avatar
  • 25.4k
2 votes
0 answers
110 views

Evidence of optimality of sieve algorithms

Sieve techniques apply to integer factoring and discrete logarithm to provide $2^{O(((\log n)(\log\log n)^2)^{1/3})}$ complexity for $n$ bit factoring and $n$ bit prime discrete logarithm. The state ...
Turbo's user avatar
  • 13.9k
1 vote
1 answer
176 views
+50

On a probabilistic integer factorization algorithm given bounds for one prime factor

We got a probabilistic integer factorization algorithm and experimental evidence with large integers given bounds for one factor. Let $D \ge 2$ be real number and let $p,q$ be primes and $N=pq$. ...
joro's user avatar
  • 25.4k
1 vote
0 answers
29 views

Factoring semiprimes via sum of two squares? [migrated]

The following thoughts came into my head after watching Grant Sanderson's JBPM award lecture here, in which he discusses the fact that we can quickly factor 3599 by noticing it can be written as (60-1)...
weissguy's user avatar
0 votes
0 answers
78 views

Factoring totient of a prime

Is it any easy to factor $p-1$ when $p$ is a prime compared to general factorization problem? What about when $2p+1$ is also a prime?
Turbo's user avatar
  • 13.9k