³4 or to-the-third-four is a positive integer equal to \(4^{4^4}\) or \(4^{256}\), four-to-the-sixteenth, with 155 digits. Its full decimal expansion is 13407807929942597099574024998205846127479365820592393377723561443721764030073546976801874298166903427690031858186486050853753882811946569946433649006084096 The superscript 3 represents tetration.