mod=10**9+7
def cmb(n,r):
  if r<0 or r>n:
    return 0
  return ((g1[n]*g2[r]%mod)*g2[n-r])%mod
 
N=5000000
g1=[1]*(N+3)
for i in range(2,N+3):
  g1[i]=g1[i-1]*i%mod
g2=[0]*len(g1)
g2[-1]=pow(g1[-1],mod-2,mod)
for i in range(N+1,-1,-1):
  g2[i]=g2[i+1]*(i+1)%mod
inv=[0]*(N+3)
for i in range(1,N+3):
  inv[i]=g2[i]*g1[i-1]%mod


H,W=map(int,input().split())
ANS=0
x=1
for i in range(H+1):
  ANS=(ANS+(x*cmb(H,i)%mod)*pow(pow(2,H-i,mod)-1,W,mod))%mod
  x=mod-x
print(ANS)