Multiexplosion refers to the function \(a \{\{\{2\}\}\} b = \{a,b,2,3\} = \underbrace{a \{\{\{1\}\}\} a \{\{\{1\}\}\} \ldots \{\{\{1\}\}\} a \{\{\{1\}\}\} a}_b\), using BEAF. In the fast-growing hierarchy, \(f_{\omega imes 2+2}(n)\) corresponds to multiexplodal growth rate.