Author Topic: Happy Prime!  (Read 7109 times)

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Offline Werechicken

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Happy Prime!
« on: November 19, 2007, 07:03:41 am »
Okay as any maths geek, or doctor who fan, knows a happy prime is both a prime number and a happy number. A prime number is any number that can only be divided by itself or 1 to give an integer (whole number). A happy number is an integer number where each of the numbers that make it up is squared then added together, then each number that makes the new total is squared and added together. This repeats until you either get 1 or it continues on an indeffinate loop. A number which give 1 is said to be a happy number. For example 7;

    7^2 = 4^9
    4^2 + 9^2 = 97
    9^2 + 7^2 = 130
    1^2 + 3^2 + 0^2 = 10
    1^2 + 0^2 = 1

So seven is both happy and a prime.

My challenge is thus, who can come up with the highest happy prime that has the lowest number of 'steps'

for example 2309 has 5 steps
2309 = 94
94 = 97
97 = 130
130 = 10
10 = 1

You should show the steps.


What have you got against intellectual midgets? They're quite smart little guys as far as i can tell.

Offline Glacies

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Re: Happy Prime!
« Reply #1 on: December 14, 2007, 11:00:49 am »
*edit* MOST PEOPLE ARE Everyone's too dumb BORING to play math games.
« Last Edit: December 17, 2007, 08:59:07 pm by Glacies »