A happy number is defined by the following process. Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers, while those that do not end in 1 are unhappy numbers (or sad numbers).
Read more about Happy Number: Overview, Sequence Behavior, Happy Primes, Special Happy Numbers, Happy Numbers in Other Bases, Cubing The Digits Rather Than Squaring, Origin, Popular Culture, Programming Example
Famous quotes containing the words happy and/or number:
“This is going to be a happy day. Another happy day.”
—Samuel Beckett (1906–1989)
“One may confidently assert that when thirty thousand men fight a pitched battle against an equal number of troops, there are about twenty thousand on each side with the pox.”
—Voltaire [François Marie Arouet] (1694–1778)