code to find the first whole number divisible by 1 to n

Greetings!!! :)

Can someone edit the following code to ask a user the number (n)?; where the code could run and find the first whole number divisible by all the numbers from 1 to n. Below example displays the first whole number which is divisible by all the numbers from 1 to 13.

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function first_whole_number
i=1;
while i>=0
    if mod(i,2)==0 && mod(i,3)==0 && mod(i,4)==0 && mod(i,5)==0 && mod(i,6)==0 && mod(i,7)==0 && mod(i,8)==0 && mod(i,9)==0 && mod(i,10)==0 && mod(i,11)==0 && mod(i,12)==0 && mod(i,13)==0
        break;
    else
    i=i+1;
    end
end
fprintf('\n\nthe first whole number divisible by 1 to 13 is %d\nThankyou\n\n\n',i);
end

**********

THANKYOU :)

Answer 1

[Looky]

the mod function accepts a vector for the second argument, you can use this to check for a sequence of factors, e.g.:

if(any(mod(i,[2:n])))
        i=i+1;
else
        break;
end    

However, this can become very slow and you might think about a more mathematical solution instead of checking every number.

[Looky]

Maybe as a little idea ... one number that will always be divisible by all numbers from 1 to n is of course n! (factorial). However, it's not the the smallest because when multiplying 1 * 2 * 3 *4 * ... * n some of these numbers will share common factors, e.g. 2 and 4. If something is divisible by 4 it is already divisible by 2 and you can strike the 2 completely in the product 1 * 3 * 4 *... *n . So instead of checking the product, you might want to think about checking the potential factors for the number in question. Hope that helps, good luck with the task.

[Athot Karmacharya]

wow!thankyou for the perfect code.

[Athot Karmacharya]

and now i modified it again without using function 'any'.