Answer:
a₀ = 0
aₙ = aₙ₋₁ + 2ⁿ⁻¹
Step-by-step explanation:
a₁ = a₀ + 2¹⁻¹ = 0 + 2⁰ = 1
a₂ = 1 + 2²⁻¹ = 3
a₃ = 3 + 2³⁻¹ = 7
..............
