# Oldboy

Laugh, and the world laughs with you. Weep, and you weep alone ("Oldboy", 2003)

Top Questions

## Punch 2000 holes in 2000 polygons with 1000 needles

asked Nov 12 '18 at 22:20

## Is the limit of this infinite step construction an equilateral triangle?

asked Sep 17 '18 at 21:12

## Another beauty hidden in a simple triangle (2)

asked Aug 25 '18 at 20:20

## Of all polygons inscribed in a given circle which one has the maximum sum of squares of side lengths?

asked Sep 17 '18 at 7:15

## Prove that $\sum_{n = 1}^{p - 1} n^{p - 1} \equiv (p - 1)! + p \pmod {p^2}$ with $p$ being an odd prime

asked Dec 31 '18 at 10:11

## Solve $\left(\frac mn\right)^k=0.\overline{x_1x_2…x_9}$ (no computers!)

asked Jan 2 '19 at 21:09

## Prove that there is $n\in\mathbb{N}$ such that $n!$ starts with 1996

asked Jun 16 '19 at 20:24

## Prove $\sum_{n = 1}^{p - 1} n^{p - 1} \equiv (p - 1)! + p \pmod {p^2}$ for $p$ being an odd prime

asked Dec 29 '18 at 11:52

## Internal angles in regular 18-gon

asked Dec 4 '18 at 10:51