#include <stdio.h>

int main()
{
    int z;
    long long int n, t, b, i, tog;

    z = 1;
    while (scanf (" %lld %lld %lld", &n, &t, &b) != EOF) {

        t = t%n;
        tog = 0LL;

        for (i = 1LL; i <= t && i*i <= b; i++) {
            if (b%i == 0) {
                if (i <= t)
                    tog++;
                if (b/i != i && b/i <= t)
                    tog++;
            }
        }
        printf("Case %d: %s\n", z++, (tog%2==0)?"Off":"On");
    }

    return 0;
}