n,a,b=map(int,input().split())
c=max(a,b)
b=min(a,b)
a=c
MOD = pow(10,9) + 7

X=1
Y=1

for i in range(1,a+1):
    X=X*(n+1-i)%MOD
    Y=Y*i%MOD
    if i==b:
        b_X=X
        b_Y=Y
a_X=X
a_Y=Y
def calc(X,Y,MOD):
    return X*pow(Y,MOD-2,MOD)

ans=pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD)

print(ans%MOD) n,a,b=map(int,input().split()) n map(int,input().split()) map int input().split() ().split () input split a b c=max(a,b) c max(a,b) max a b b=min(a,b) b min(a,b) min a b a=c a c MOD = pow(10,9) + 7 MOD pow(10,9) + 7 pow(10,9) pow 10 9 7 X=1 X 1 Y=1 Y 1 for i in range(1,a+1):
    X=X*(n+1-i)%MOD
    Y=Y*i%MOD
    if i==b:
        b_X=X
        b_Y=Y i range(1,a+1) range 1 a+1 a 1 X=X*(n+1-i)%MOD X X*(n+1-i)%MOD X*(n+1-i) X n+1-i n+1 n 1 i MOD Y=Y*i%MOD Y Y*i%MOD Y*i Y i MOD if i==b:
        b_X=X
        b_Y=Y i==b i b b_X=X b_X X b_Y=Y b_Y Y a_X=X a_X X a_Y=Y a_Y Y def calc(X,Y,MOD):
    return X*pow(Y,MOD-2,MOD) calc return X*pow(Y,MOD-2,MOD) X*pow(Y,MOD-2,MOD) X pow(Y,MOD-2,MOD) pow Y MOD-2 MOD 2 MOD X X Y Y MOD MOD ans=pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD) ans pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD) pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD) pow(2,n,MOD)%MOD-1 pow(2,n,MOD)%MOD pow(2,n,MOD) pow 2 n MOD MOD 1 calc(a_X,a_Y,MOD) calc a_X a_Y MOD calc(b_X,b_Y,MOD) calc b_X b_Y MOD print(ans%MOD) print ans%MOD ans MOD Y=1 1 Y b_X=X X b_X n,a,b=map(int,input().split()) map(int,input().split()) n b=min(a,b) min(a,b) b c=max(a,b) max(a,b) c a,b=map(int,input().split()) map(int,input().split()) a X=1 1 X Y=Y*i%MOD Y*i%MOD Y b=map(int,input().split()) map(int,input().split()) b a_Y=Y Y a_Y b_Y=Y Y b_Y MOD = pow(10,9) + 7 pow(10,9) + 7 MOD a=c c a X=X*(n+1-i)%MOD X*(n+1-i)%MOD X ans=pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD) pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD) ans a_X=X X a_X def calc(X,Y,MOD):
    return X*pow(Y,MOD-2,MOD) def calc(X,Y,MOD):
    return X*pow(Y,MOD-2,MOD) calc
n,a,b=map(int,input().split())
c=max(a,b)
b=min(a,b)
a=c
MOD = pow(10,9) + 7

X=1
Y=1

for i in range(1,a+1):
    X=X*(n+1-i)%MOD
    Y=Y*i%MOD
    if i==b:
        b_X=X
        b_Y=Y
a_X=X
a_Y=Y
def calc(X,Y,MOD):
    return X*pow(Y,MOD-2,MOD)

ans=pow(2,n,MOD)%MOD-1-calc(a_X,a_Y,MOD)-calc(b_X,b_Y,MOD)

print(ans%MOD)
