#include <stdio.h>

int numbers_game(int min, int max)
{
    int counter, c = min;

    if (max - min == 1) return min * max;
    if (min == 1)
    {
        min = 1;
        counter = 1;
        while (min != max)
        {
            min += 1;
            if (counter % min != 0)
            {
                if (min % 2 == 0) counter *= 2;
                else if (min % 3 == 0) counter *= 3;
                else counter *= min;
            }
        }

        return counter;
    }
    else
    {
        counter = max;
        while (1)
        {
            min = c;
            while (min != max + 1)
            {
                if (counter % min != 0) break;
                if (min == max ) return counter;
                min += 1;
            }
            counter += max;
        }
    }
}

int main(void)
{
    int min, max;

    scanf("%d%d", &min, &max);
    printf("%d", numbers_game(min, max));

    return 0;
}