Project Euler 5 - Smallest multiple

2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.

What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?

Official link: https://projecteuler.net/problem=5

Thought Process

We can take the biggest prime factors from 11-20 and multiply them

20 = 2^2 * 5

19 = 19

18 = 2 * 3^2

17 = 17

16 = 2^4

15 = 3 * 5

14 = 2 * 7

13 = 13

11 = 11

Answer = 11 * 13 * 7 * 5 * 2^4 * 17 * 3^2 * 19


Or we can continuously take the lcm, for example a = lcm(20,19), b = lcm(a,18), etc

Interactive Code

Enter a number (yourinput)

Code will output the lcm from 1 till yourinput