The following iterative sequence is defined for the set of positive integers:
Project Euler Problem 11 (Greatest product of four adjacent numbers in any direction in a 20 by 20 grid)
In the 20×20 grid below, four numbers along a diagonal line have been marked in red.
2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten terms would be:
The prime factors of 13195 are 5, 7, 13 and 29.
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.
A Pythagorean triplet is a set of three natural numbers, a < b < c, for which,
By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total from top to bottom is 23.