Translation of "tetration" into Portuguese

(arithmetic) The arithmetic operator consisting of repeated exponentiation, by analogy with exponentiation being repeated multiplication and multiplication being repeated addition, ^b a denoting a to the power of a to the power of ... to the power of a , in which a appears b times. Notation: ^b a , a\uparrow\uparrow b or a\rightarrow b\rightarrow 2 [..]