tetration

tetration englanniksi

1. 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''↑↑''b'' or ''a''→''b''→2