class NCK:
    '''
    最大値 :N
    mod
    '''
    def __init__(self,N,mod):
        self.mod = mod
        self.N = N
        self.factmod = [1,1]
        for i in range(2,self.N+1):
            self.factmod.append((self.factmod[-1]*i)%self.mod)

        self.inv = [0,1]
        for i in range(2, N + 1):
            self.inv.append((-self.inv[self.mod % i] * (self.mod // i)) % self.mod)

        self.invfact = [1,1]
        for i in range(2, N + 1):
            self.invfact.append((self.invfact[-1]*self.inv[i])%self.mod)

    def nCk(self,a,b):
        if a < b:
            return 0
        return ((self.factmod[a]*self.invfact[b]%self.mod)*self.invfact[a-b])%self.mod
    
    def invnCk(self,a,b):
        return ((self.factmod[a-b]*self.invfact[a]%self.mod)*self.factmod[b])%self.mod

N = int(input())
lsa = list(map(int,input().split()))
ans = 0
mod = 10**9+7
nck = NCK(10**5+1, 10**9+7)
for i in range(N):
    ans += nck.nCk(N-1, i) * lsa[i]
    ans %= mod
print(ans)