The sequence 2,3,5,8,13,21,…2, 3, 5, 8, 13, 21, \ldots2,3,5,8,13,21,… follows which recurrence relation?
an=an−1+1a_n = a_{n-1} + 1an=an−1+1
an=an−1+an−2a_n = a_{n-1} + a_{n-2}an=an−1+an−2
an=2an−1−an−2a_n = 2a_{n-1} - a_{n-2}an=2an−1−an−2
an=an−1+an−2+1a_n = a_{n-1} + a_{n-2} + 1an=an−1+an−2+1