Questions tagged [semiprimes]
A semiprime is a natural number that is the product of two prime numbers. This tag is intended for questions about, related to, or involving semiprime numbers.
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Is a sequence of 4 or more consecutive semiprimes possible?
By observing sequences of consecutive integers having the same number of prime factors, I noticed that there never seem to be more than 3 consecutive semiprimes. Does anyone have an idea of what might ...
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Conjecture on odd numbers producing (semi) primes
While playing around with numbers, I noticed the following pattern: the sum of two consecutive odd numbers added with the product of said numbers produce a prime or a semi-prime. That is, for any two ...
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Can I use the slope of $\sqrt{N}$ to factor semiprimes? I get an equivalence if I try. How can I use related rates?
I need to make two definitions before I get to my question, which is at the bottom.
Domain: is the X-axis (variable)
Range: is the Y-axis
$$f(Domain) = Range$$
I think semiprimes can be factored by ...
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What is range of $P$ values and range of $Q$ values for any given semiprime $N$?
Given $PQ = N$ where $P<Q$ and both $P$ and $Q$ are odd. I determined that the range of values for $P$ is: $\frac{\sqrt{N}}{2} < P \le \sqrt{N}$ and the range of values for $Q$ is: $\sqrt{N} <...
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reciprocals of squarefree k-almost primes
First of all, I'm a novice in math and English is not my native language, so I apologize in advance for any incorrect wording, etc.
Definitions and specific example
Let's define the set $A_4 = \{2,3,5,...
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Chen’s Theorem with conditional semiprimes
Chen’s Theorem states that every sufficiently large even integer can be written as the sum of a prime and a prime or a semiprime (the product of two, not necessarily distinct, primes). Let’s consider ...
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Complexity of detecting a semiprime
A semiprime is a number that factors into exactly two primes. The decision problem SEMIPRIME decides whether a given number is a semiprime.
It follows from the polynomiality of the AKS test that ...
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Does knowing "sqrt(-1) mod n" for semiprime n=p*q with p=1 (mod 4) and q=1 (mod 4) allow to efficiently factor n?
This is a follow up on "Euler's factorization needs two different sums of squares, what if only one sum of squares is known?":
Euler's factorization needs two different sums of squares, ...
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Euler's factorization needs two different sums of squares, what if only one sum of squares is known?
Euler's factorization determines prime factors if two different sums of squares of number $n$ are given.
I just did that in Python not knowing Euler's method:
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Are there infinitely many primes of the form $y = 2p_1p_2 + 1$?
I came up with this (I admit I'm probably not the first one to have this thought but I haven't been able to find anyone else with the same question) while reading about semiprimes.
Clearly $y$ is ...
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Proof n is semi-prime using Pollard-rho
I wrote some code determining whether a number n is square free, and decided I want to make it as fast as I can. A number that isn't square free is either a square or the product of at least three ...
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Questions of difference of integer squares being semiprime
I searched a lot, but found no answers to my questions.
I am interested in difference of integer squares being semiprime (RSA number) and posted about:
Odd prime iff unique difference of 2 squares
Is ...
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Best algorithm to tell if an odd semi prime exists between a given pair of even semi primes.
Problem:
Let two even semi primes be $2q_1$ and $2q_2$:
you are to find if any $n$ exists such that $n$ is odd , $n$ is semi-prime and $2q_1 < n < 2q_2$. We don't need to know the $n$ , we just ...
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Query on $3^x \pm 2^{x-a}$ with relation to prime and semiprime
While doing some research(more closer to some playing) with the formula $3^x\pm2^{x-a}$ for $x\in \mathbb{N}$ and $ \{a\mid a \in \mathbb{Z}_{\geq 0},\hspace{1mm} a\le (x-1)\}$ I've become to observe ...
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For $x+y=2p, p \in \mathbb{P}$, there are visible points $v=p-1$.
Conjecture
For $x+y=2p, p \in \mathbb{P}$, there are visible points $v=p-1$.
Example
Let $p=7$, then $v=6$.
Similarly for
$p=11 \rightarrow v=10$
$p=13 \rightarrow v=12$
$p=17 \rightarrow v=16$
...
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