New posts in Recreational Mathematics

Show that there are infinitely many natural numbers such that $a^2+b^2=c^2+3 .$

Probability that girl who answers the door is the eldest girl?

Expected time to fuse a $D_{10}$ dragon

In a club with 99 people, everyone knows at least 67 people. Prove there's a group of 4 people where everyone knows each other

Is it possible to cover an $11 \times 12$ rectangle with $19$ rectangles of $1 \times 6$ or $1 \times 7$?

What is so funny about sin($\alpha+\beta$) versus sin(s+i+n)?

Find the number of magical grids.

Can you find your location in $\mathbb{Z}$ using least prime factor?

Why $142857$ when multiplied by $1$ to $6$ gives the same digits?

Maximum run in binary digit expansions