N,A,B=map(int,input().split())
p=10**9+7
def cmb(n,k):
    x,y = 1,1
    for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
    return x*pow(y,p-2,p)%p
print((pow(2,N,p)-cmb(N,A)-cmb(N,B)-1)%p) N,A,B=map(int,input().split()) N map(int,input().split()) map int input().split() ().split () input split A B p=10**9+7 p 10**9+7 10**9 10 9 7 def cmb(n,k):
    x,y = 1,1
    for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
    return x*pow(y,p-2,p)%p cmb x,y = 1,1 x 1 y 1 for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
     i range(k) range k x=x*(n-i)%p x x*(n-i)%p x*(n-i) x n-i n i p y=y*(i+1)%p y y*(i+1)%p y*(i+1) y i+1 i 1 p return x*pow(y,p-2,p)%p x*pow(y,p-2,p)%p x*pow(y,p-2,p) x pow(y,p-2,p) pow y p-2 p 2 p p n n k k print((pow(2,N,p)-cmb(N,A)-cmb(N,B)-1)%p) print (pow(2,N,p)-cmb(N,A)-cmb(N,B)-1)%p pow(2,N,p)-cmb(N,A)-cmb(N,B)-1 pow(2,N,p)-cmb(N,A)-cmb(N,B) pow(2,N,p)-cmb(N,A) pow(2,N,p) pow 2 N p cmb(N,A) cmb N A cmb(N,B) cmb N B 1 p N,A,B=map(int,input().split()) map(int,input().split()) N B=map(int,input().split()) map(int,input().split()) B def cmb(n,k):
    x,y = 1,1
    for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
    return x*pow(y,p-2,p)%p def cmb(n,k):
    x,y = 1,1
    for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
    return x*pow(y,p-2,p)%p cmb p=10**9+7 10**9+7 p A,B=map(int,input().split()) map(int,input().split()) A
N,A,B=map(int,input().split())
p=10**9+7
def cmb(n,k):
    x,y = 1,1
    for i in range(k):
        x=x*(n-i)%p
        y=y*(i+1)%p
    return x*pow(y,p-2,p)%p
print((pow(2,N,p)-cmb(N,A)-cmb(N,B)-1)%p)