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:
“There is the grand truth about Nathaniel Hawthorne. He says NO! in thunder; but the Devil himself cannot make him say yes. For all men who say yes, lie; and all men who say no,why, they are in the happy condition of judicious, unincumbered travellers in Europe; they cross the frontiers into Eternity with nothing but a carpet-bag,that is to say, the Ego. Whereas those yes-gentry, they travel with heaps of baggage, and, damn them! they will never get through the Custom House.”
—Herman Melville (18191891)
“That country is the richest which nourishes the greatest number of noble and happy human beings.”
—John Ruskin (18191900)