if a1 = 4 and an = -2an -1 then find the value of a5

Answer 1

a₁ = 4

a₂ = -2(a₁) - 1

a₂ = -2(4) - 1

a₂ = -9

a₃ = -2(a₂) - 1

a₃ = -2(9) - 1

a₃ = -19

Can you do a₄ and a₅ and answer?