Which of these recursive formulas defines the sequence 1,4,7,10,…1, 4, 7, 10, \dots1,4,7,10,…?
an=an−1+3,a1=1a_n = a_{n-1} + 3, a_1 = 1an=an−1+3,a1=1
an=an−1+1,a1=4a_n = a_{n-1} + 1, a_1 = 4an=an−1+1,a1=4
an=3an−1,a1=1a_n = 3a_{n-1}, a_1 = 1an=3an−1,a1=1
an=an−1+4,a1=1a_n = a_{n-1} + 4, a_1 = 1an=an−1+4,a1=1