If a1=5,a2=10,a3=15a_1 = 5, a_2 = 10, a_3 = 15a1=5,a2=10,a3=15, then an=a_n = an=:
n+5n+5n+5
5n5n5n
5n−55n - 55n−5
n5n^5n5