Which of the following is true for an=2an−1+1a_n = 2a_{n-1} + 1an=2an−1+1 with a0=0a_0=0a0=0?
an=2n−1a_n = 2^n - 1an=2n−1
an=2n+1a_n = 2^n + 1an=2n+1
an=2n+1−1a_n = 2^{n+1} - 1an=2n+1−1
an=2na_n = 2^nan=2n