User blog comment:Ikosarakt1/Factorials/@comment-5150073-20120530180749/@comment-37556263-20191031221637

I initially thought those superscripts referred to what power the factorials were raised to. Maybe this would be more intuitive, given there's no explanation for the notation itself:


 * Tetrafactorial n!4
 * Pentafactorial n!5
 * Hexafactorial n!6
 * Heptafactorial n!7
 * Octafactorial n!8
 * Enneafactorial n!9
 * Decafactorial n!10