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Empy2
  • Member for 9 years
  • Last seen this week
  • Adelaide, Australia
34 votes
Accepted

Prove there are no prime numbers in the sequence $a_n=10017,100117,1001117,10011117, \dots$

30 votes
Accepted

question about prime numbers

28 votes

Why did Euler use e to represent complex numbers?

27 votes

What is the limit of $x/(x+\sin x)$ as $x$ approaches infinity?

22 votes
Accepted

Understanding this pattern behind the Fibonacci sequence

20 votes
Accepted

Calculate the limit : $\lim_{x \to 0}\frac{x-\sin{x}}{x^3}$ WITHOUT using L'Hopital's rule

19 votes
Accepted

Check if a point is inside a rectangular shaped area (3D)?

16 votes
Accepted

Inequality involving square roots

16 votes
Accepted

Is it possible for the bisection method to provide "fake" zeros

15 votes
Accepted

What does $\|u\|$ mean?

15 votes

Intermediate digits of 34!

15 votes

What is the average rational number?

13 votes
Accepted

Is $x = 2$ is the only real solution for $a^x + b^x = c^x$ when $(a,b,c)$ is a pythagorean triplet?

13 votes

If squaring a number means multiplying that number with itself then shouldn't taking square root of a number mean to divide a number by itself?

12 votes

Sum of cubes of first n fibonacci numbers

12 votes
Accepted

Probability of getting a $7$ in Minesweeper

12 votes

Why do reciprocal functions work for undefined values?

12 votes

How would you prove that there is only a finite number of these primes?

11 votes

Is it true that every eigenvalue has at least one eigenvector?

11 votes

Calculating decimal digits by hand for extremely large numbers

11 votes

If $f(x)=f(2x)$, then $f$ is differentiable

11 votes

Why does $f(z) = z^n$ have no antiderivative only for $n=-1$?

10 votes

What are your favorite relations between e and pi?

10 votes
Accepted

Special about 2015 with conjecture?

10 votes

Prove that $A_{100} \gt 14$ where $A_{n}=A_{n-1}+\frac{1}{A_{n-1}}$ and $A_1=1$

10 votes
Accepted

Question about GIMPS (Great Internet Mersenne Prime Search)

10 votes

For which $n\in\Bbb N$ can we divide $\{1,2,3,...,3n\}$ into $n$ subsets each with $3$ elements such that in each subset $\{x,y,z\}$ we have $x+y=3z$?

10 votes

If I ask $1000$ people to choose a random number between $0$ and $999$, what is the probability that no one will choose a specific number?

10 votes

Calculating $1+\frac13+\frac{1\cdot3}{3\cdot6}+\frac{1\cdot3\cdot5}{3\cdot6\cdot9}+\frac{1\cdot3\cdot5\cdot7}{3\cdot6\cdot9\cdot12}+\dots? $

9 votes
Accepted

if $\alpha$ $\beta$ and $\gamma$ are the roots of a equation than find the value of .

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