a⁷ · (a⁴)⁶ : (a³)⁵ = a⁷ · a²⁴ : a¹⁵ = a⁷ ⁺ ²⁴ ⁻ ¹⁵ = a¹⁶
a^7*(a^4)^6:(a^3)^5 = a^7*a^24:a^15 = a^31:a^15 = a^16
