Indian mathematician Nārāyaṇa (1356) is the originator of the “Inscribed Lotus” (*Padma Vrtta*, a magic diagram constructed with the numbers of the 12×4 magic rectangle), in which every group of 12 numbers has the same sum **294**.

### A Paradoxical Zero-Length Hypotenuse

A strange right-triangle involving the unit imaginary number *i*

### Sacred Geometry

Repeated barycentric subdivision results in a gorgeous fractal-ish pattern.

### Impossible Structure

Perpetual Escher’s waterfall

### Toeplitz’ Conjecture

### Four Constants in Four 4’s

The infamous problem of representing numbers with four 4’s appeared for the first time in 1881 in a London science journal. In 2001, a team of mathematicians from Harvey Mudd College found that we can even get four 4’s to approximate four notable constants: the ** number e**,

*,*

**π***, and*

**acceleration of gravity***.*

**Avogadro’s number**### Six Points on a Circle

Take 6 points on a circle such that every second edge (green chords) has length equal to the radius of the circle. Then the midpoints of the other three sides of the cyclic hexagon form an equilateral triangle.

Read more: https://www.archimedes-lab.org/2-Sunday_puzzle_43.html

### Geometric Passe-muraille

A 3D regular hexahedron solid (cube) passing through a 2D plane:

### Isogonic Center

In geometry, the **isogonic center** (aka Fermat–Torricelli point) of a triangle, is a point such that the total distance from the three vertices of the triangle to the point is the minimum possible.

### Math Hack of the Day: 66 + 99 = ?

Maths à la De Funès…