Question

A sequence is defined recursively as follows. What is the value of a6 ?

Answer 1

If a₁ = 5 and $a_{n+1}=a_n-3$, then

a₂ = a₁ - 3 = 5 - 3 = 2

a₃ = a₂ - 3 = 2 - 3 = -1

a₄ = a₃ - 3 = -1 - 3 = -4

a₅ = a₄ - 3 = -4 - 3 = -7

a₆ = a₅ - 3 = -7 - 3 = -10