Project Euler — Problem 92 Solution

Problem

A number chain is created by continuously adding the square of the digits in a number to form a new number until it has been seen before.

For example,

Therefore any chain that…

Project Euler — Problem 87 Solution

Problem

The smallest number expressible as the sum of a prime square, prime cube, and prime fourth power is 28. In fact, there are exactly four numbers below fifty that can be expressed in such a way: