Which closed-form solution satisfies the recurrence an=2an−1−an−2a_n = 2a_{n-1} - a_{n-2}an=2an−1−an−2 with a0=1a_0 = 1a0=1 and a1=3a_1 = 3a1=3?
an=1+2na_n = 1 + 2nan=1+2n
an=2n+1a_n = 2n + 1an=2n+1
an=n2+n+1a_n = n^2 + n + 1an=n2+n+1
an=3⋅2n−5a_n = 3 \cdot 2^n - 5an=3⋅2n−5