Problems

• Problem 1 - Add all the natural numbers below one thousand that are multiples of 3 or 5

• Problem 2 - By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms
• Problem 3 - Find the largest prime factor of a composite number
• Problem 4 - Find the largest palindrome made from the product of two 3-digit numbers
• Problem 5 - What is the smallest number divisible by each of the numbers 1 to 20?
• Problem 6 - What is the difference between the sum of the squares and the square of the sums?
• Problem 7 - Find the 10001st prime
• Problem 8 - Discover the largest product of five consecutive digits in the 1000-digit number
• Problem 9 - Find the only Pythagorean triplet, {a, b, c}, for which a +b + c = 1000
• Problem 10 - Calculate the sum of all the primes below two million
• Problem 13 - Work out the first ten digits of the sum of the following one-hundred 50-digit numbers
• Problem 14 - Find the longest sequence using a starting number under one million.
• Problem 16 - What is the sum of the digits of the number 2¹⁰⁰⁰?
• Problem 20 - Find the sum of digits in 100!

---