New posts in recreational-mathematics

How can a piece of A4 paper be folded in exactly three equal parts?

Proving you *can't* make $2011$ out of $1,2,3,4$: nice twist on the usual

Where is the flaw in this "proof" that 1=2? (Derivative of repeated addition)

Is this sufficient condition for infinite number generation from a finite seed also a necessary one?

Product of $k$ factors as linear combination of linear combinations of its factors that are raised to the power of $k$

"Integral Milking"

Can you answer my son's fourth-grade homework question: Which numbers are prime, have digits adding to ten and have a three in the tens place?

What is the maximum volume that can be contained by a sheet of paper?

The Mathematics of Tetris

Calculating the length of the paper on a toilet paper roll

"The Egg:" Bizarre behavior of the roots of a family of polynomials.

How long will it take Marie to saw another board into 3 pieces?

Visually stunning math concepts which are easy to explain