#include<bits/stdc++.h>

#define ll long long
#define fi first
#define se second
#define mkp make_pair
#define pb push_back
#define gc getchar
#define pc putchar
#define pii pair<int,int>
#define For(i,l,r) for(int i=(l);i<=(r);i++)
#define for_son(u) for(int e=head[u];e;e=nxt[e])
#define eps (1e-8)
#define INF 0x3f3f3f3f

using namespace std;

char aa;

namespace ljh
{

namespace IO
{
	const int SIZ=1<<20;
	char ibuf[SIZ],*p1,*p2,obuf[SIZ],*p3=obuf;
//	#define gc() (p1==p2&&(p2=(p1=ibuf)+fread(ibuf,1,SIZ,stdin),p1==p2)?EOF:*p1++)
//	il void pc(const char &c)
//	{
//		if(p3-obuf==SIZ) fwrite(obuf,1,SIZ,stdout),p3=obuf;
//		*p3++=c;
//	}
	inline int rd()
	{
		int x=0,f=1;
		char ch=gc();
		while(!isdigit(ch)){
			if(ch=='-') f=-1;
			ch=gc();
		}
		while(isdigit(ch)){
			x=x*10+ch-'0';
			ch=gc();
		}
		return x*f;
	}
	inline void wr(int x,char ch)
	{
		if(x<0) x=-x,pc('-');
		static char st[12];
		int top=0;
		do{
			st[top++]=x%10+'0',x/=10;
		}while(x);
		while(top) pc(st[--top]);
		pc(ch);
	}
	inline ll ll_rd()
	{
		ll x=0;
		int f=1;
		char ch=gc();
		while(!isdigit(ch)){
			if(ch=='-') f=-1;
			ch=gc();
		}
		while(isdigit(ch)){
			x=x*10+ch-'0';
			ch=gc();
		}
		return x*f;
	}
	inline void ll_wr(ll x,char ch)
	{
    	if(x<0) x=-x,pc('-');
		static char st[22];
		int top=0;
		do{
			st[top++]=x%10+'0',x/=10;
		}while(x);
		while(top) pc(st[--top]);
		pc(ch);
	}

	inline int qpow(int a,int b,int p)
	{
		a%=p;
		int res=1;
		while(b){
			if(b&1) res=1ll*res*a%p;
			a=1ll*a*a%p;
			b>>=1;
		}
		return res;
	}

//	inline void add_edge(int u,int v)
//	{
//		nxt[++cnt]=head[u];
//		to[cnt]=v;
//		head[u]=cnt;
//	}
}

using namespace IO;

const int N=1e5+5,mod=0;

struct Node{
	int d,u,v;
	ll val;
};

struct cmp{
	bool operator () (const Node &a,const Node &b)
	{
		return a.val>b.val;
	}
};

int n,L,R,fa[N];
ll ans;
priority_queue<Node,vector<Node>,cmp>q;

int get(int x)
{
	return fa[x]==x?x:fa[x]=get(fa[x]);
}

void main()
{
	L=rd(),R=rd(),n=R-L+1;
	For(i,1,n) fa[i]=i;
	For(d,1,n){
		int st=(L+d-1)/d*d;
		if(st+d<=R) q.push(Node{d,st,st+d,1ll*st/d*st+st});
	}
	while(!q.empty())
	{
		Node t=q.top();
		q.pop();
		int d=t.d,u=t.u,v=t.v;
		ll val=t.val;
		int su=get(u-L+1),sv=get(v-L+1);
		if(su!=sv) fa[su]=sv,ans+=val;
		if(v+d<=R) q.push((Node){d,u,v+d,val+u});
	}
	ll_wr(ans,'\n');
//	fwrite(obuf,1,p3-obuf,stdout);
}

/*
*/

}

char bb;

int main()
{
//	freopen("1.in","r",stdin);
//	freopen("1.out","w",stdout);
	ljh::main();
//	cerr<<(&bb-&aa)/1024/1024<<endl;
//	fclose(stdin);
//	fclose(stdout);
	return 0;
}