思路：

 代码：

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
const double eps = 1e-8;
const int N = 1e7+10;
const long long  mod = 20101009;
#define LL long long 
int pre[N],st[N];
int n,cn,m;
LL mu[N];
LL g(int l, int k)
{
    return (LL)k / (k / l);
}
void into()
{
    mu[1] = 1;
    for (int i = 2; i <= N; i++)
    {
        if (!st[i]) pre[++cn] = i, mu[i] = -1;
        for (int j = 1; pre[j] * i <= N&&j<=cn; j++)
        {
            st[pre[j] * i] = 1;
            if (i % pre[j] == 0) break;
            mu[i*pre[j]] = -mu[i];
        }
    }
    for (int i = 1; i <= N; i++)
        mu[i] = ((LL)mu[i]*i%mod*i%mod+mu[i - 1])%mod;
}
LL gd(int l, int r)
{
    return (LL)(r - l + 1) * (r + l) / 2%mod;
}
LL f(int n, int m)
{
    LL res = 0;
    for (int r,l = 1; l <= n; l = r + 1)
    {
        r =  min(n,(int)min(g(l, n), g(l, m)));
        res = (res + (LL)(mu[r] - mu[l - 1]) * gd(1,n/l) % mod *gd(1,m/l)% mod) % mod;
    }
    return res;
}
int main()
{
    into();
    cin >> n >> m;
    if (n >m)swap(n, m);
    LL ans = 0;
    for (int r,l = 1; l <= n; l = r + 1)
    {
        r =  min(n,(int)min(g(l, n), g(l, m)));
        ans = (ans + (LL)gd(l,r)% mod * (LL)f(n / l, m / l) % mod) % mod;
   }
    cout << (ans % mod + mod) % mod << endl;
    return 0;
}