To mark with an asterisk. Usage Note: The phonological phenomenon of metathesis involves the transposition of sounds or syllables in a word. Metathesis is responsible for the common rendering of ask as aks or ax. (This issue is discussed comprehensively at ax.) Similarly, one sometimes hears asterisk pronounced with the sk transposed to produce a (ks) sound, as though the word were spelled asterix or astericks.
Given an Euler brick with edges (a, b, c), the triple (bc, ac, ab) constitutes an Euler brick as well. Perfect cuboid Template:Unsolved A perfect cuboid (also called a perfect box) is an Euler brick whose body diagonal is also an integer.
Euler was also the first to use the letter e for it in 1727 (the fact that it is the first letter of his surname is coincidental). As a result, sometimes e is called the Euler Number, the Eulerian Number, or Napier's Constant. It was proven by Euler that e is an irrational number, so its decimal expansion never terminates, nor is it ever periodic. An effective way to calculate the value of e is not to use the defining equation above, but to use.