ELI5: Explain Like I'm 5

Taxicab number

Hey there kiddo! Have you ever taken a ride in a taxi before and noticed the numbers on the car? Those numbers are called taxicab numbers!

But a taxicab number is more than just a number on a car. It's actually a special type of number that can be written as the sum of two cubes in two different ways.

Let's break that down a bit. A cube is simply a number that is multiplied by itself three times. So, for example, 2 cubed (written as 2^3) is 2 x 2 x 2, which equals 8.

Now, a taxicab number is a number that can be written as the sum of two cubes in two different ways. For example, the number 1729 is a taxicab number because it can be written as the sum of two cubes in two different ways:

1. 1729 = 1^3 + 12^3
2. 1729 = 9^3 + 10^3

These two different ways of writing 1729 as the sum of two cubes are what makes it a taxicab number.

Pretty cool, huh? Math can be fun and surprising sometimes!