The combustion of the hydrogen and of the oxygen at the point of the cylinder produces solely the vapor or steam of water. Five Weeks in a Balloon by Verne, Jules View in context.
Factorial number system. In combinatorics, the factorial number system, also called factoradic, is a mixed radix numeral system adapted to numbering permutations. It is also called factorial base, although factorials do not function as base, but as place value of digits.
A factorion is a natural number that equals the sum of the factorials of its decimal digits. For example, 145 is a factorion because 1! + 4! + 5! = 1 + 24 + 120 = 145. There are just four factorions (in base 10) and they are 1, 2, 145 and 40585 (sequence A014080 in the OEIS).