N,M=map(int,input().split())
ans=0
s=0
D=[0]*(N+1)
for m in range(1,M+1):
    for n in range(m,N+1,m):
        D[n]+=m
for n in range(1,N+1):
    s+=M-D[n]
    ans=max(ans,s)
print(ans)