MOD = 10 ** 9 + 7
N = int(input())
A = list(map(int, input().split()))
dp = [0] * N
dp[0] = 1
for i in range(N - 1):
    dp[i + 1] += dp[i]
    dp[i + 1] %= MOD
    for j in range(i + A[i], N, A[i]):
        if j != i + 1:
            dp[j] += dp[i]
            dp[j] %= MOD
    # print(dp)
print(dp[N - 1])