Pentation

• abstract: Pentation is the operation of repeated tetration, just as tetration is the operation of repeated exponentiation. It is a hyperoperation and is non-commutative, and therefore has two inverse functions, which might be named the penta-root and the penta-logarithm (analogous to the two inverse functions for exponentiation: nth root function and logarithm).

以上来源于: WordNet