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2 votes
0 answers
173 views

Question about the collection of the prime factors of a fibonacci number

A positive integer $n$ is called pandigital , if every digit from $0$ to $9$ occurs in the decimal expansion of $n$. Conjecture : The largest non-pandigital fibonacci-number (a fibonacci-number with ...
Peter's user avatar
  • 85.1k
4 votes
1 answer
120 views

If $p$ can divide $a^n+b^n+c^n$ , can $p^k$ divide it as well?

Related to this Is there a method to decide whether a given function of the form $f(n)=a^n+b^n+c^n$ ($a,b,c$ fixed positive integers , $n$ running over the positive integers) satisfies the following ...
Peter's user avatar
  • 85.1k
3 votes
0 answers
131 views

Beal's conjecture $A^x+B^y=C^z$

Beal's conjecture is a generalization of Fermat's Last Theorem. It states: If $A^x + B^y = C^z$, where $A, B, C, x, y$ and $z$ are positive integers and $x, y$ and $z$ are all greater than $2$, then $...
user824546's user avatar
4 votes
0 answers
114 views

Conjecture on the sum of prime factors

$\text{Notations}$ Let $\pi(n)$ be the prime counting function. Let denote $\alpha(n)$ the sum of the prime factors of $n$. (i.e. In other words, if $$n=p_1^{x_1}p_2^{x_2}...p_m^{x_m}$$ then $\alpha(n)...
user avatar
2 votes
1 answer
167 views

Conjecture on $\pi(n)$ and other arithmetic functions

$\text{Notations}$ Let $\pi(n)$ be the prime countiong function. Let $\alpha(n)$ denote the number of prime factors of $n$ and $\beta(n)$ the sum of the prime factors of $n$. In other words, if $$n=...
user avatar
2 votes
1 answer
184 views

The equation $\varphi(n)=n-\log_2(1+\operatorname{gpf}(n))-\operatorname{gpf}(n)+1$ and Mersenne primes

Let $n\geq 1$ an integer, we denote the Euler's totient function as $\varphi(n)$ and the greatest prime dividing $n$ as $\operatorname{gpf}(n)$ (that it the arithmetic function defined in the ...
user avatar
0 votes
1 answer
191 views

For all $n$, $9^n + 25^n - 1$ has a prime factor with $7$ in its decimal representation?

Let $x_n$ be a sequence of positive integers defined by $x_n=9^n + 25^n -1$ for all $n \ge 2$ I conjectured that there exists at least one prime divisor of $x_n$ which contains $7 $ in its decimal ...
UtsabrajSarkar's user avatar