[(2^(3n+2) : 8^n]^2 + [3^(2n + 1) × 8^n] : [9^n × 2^(3n)] =
= [(2^(3n+2) : (2^3)^n]^2 + [3^(2n+1) × (2^3)^n] : [(3^2)^n × 2^(3n)] =
= [(2^(3n+2) : 2^(3n)]^2 + [3^(2n+1) × 2^(3n)] : [3^(2n) × 2^(3n)] =
= (2^2)^2 + (3 × 1) =
= 2^4 + 3 =
= 16 + 3 =
= 19