What is the algorithm of this?

Question

2520 is the least integer divisible by numbers 1 to 10. Write a java programme to find the least divisible integer by numbers 1 to 20

Answer 1

● That will be LCM {1,2,3, ...,10}
// I believe you want least +ve integer, else 0 and -ve integer can also satisfy the condition.
● fast way to do it, 1,2,3,4,5 comes as factors in 6,8,9 & 10. so you can exclude those 1,2,3,4,5 as will get counted in 6, 8, 9, 10.
so LCM{1, 2, 3, ..., 10} will be reduced to LCM{6, 7, 8, 9, 10}.
● After that you can Find LCM of those numbers.

Answer 2

Go through these links :
● How to find LCM : http://www.math.com/school/subject1/lessons/S1U3L3DP.html
● Finding LCM of multiple numbers : https://www.geeksforgeeks.org/lcm-of-given-array-elements/amp/
● one more way : https://www.geeksforgeeks.org/finding-lcm-two-array-numbers-without-using-gcd/amp/
//I don't know much of algorithm, but I believe we only need definition of LCM & give it a try with making our logic after some observations.
//so I advice you to see 1st link only 👍
● see my above comment also for reducing the number of elements of which you have to find LCM. use % operator for that.