Board 8 > Take a number and raise it to the fifth power

(+) Yeah! (+)

Make a note of the last digit of your original number
See the last digit of the new number
They're the same

OOOOOHHHHHHHH

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senorhousemouse

I just came

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One Piece: Pirates with style!
-= Metal Gear Solid: Tactical Espionage Action =-

HOW IS THIS POSSIBLE

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SuperNiceDog - 1, pjbasis - 0

Eoin posted...
Works with ninth powers as well.

WHOAMG mind kasploded

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PSN: JDTAY87

Works with ninth powers as well (and every 4 powers, such as 13th power, 17th power, etc.).

Considering that a lot of digits work on this principle on any power or on any odd-numbered power, this isn't really that amazing.

xxx1^anything => xxx1
xxx2^5 = xxx2
xxx3^5 = xxx3
xxx4^3 = xxx4
xxx5^anything => xxx5
xxx6^anything => xxx6
xxx7^anything => xxx7
xxx8^5 => xxx8
xxx9^3 => xxx9
xxx0^anything => xxx0


There's a very simple reason for this, too. Even + Even = Even. Odd * Odd = Odd. Therefore you only have five choices for last digit. And numbers ending in 5 or 0 are strictly multiples of 5, so any number not already a multiple of 5 can't become one by being raised to a power. So really, you only have 4 choices. So you get a cycle of 1, 2, or 4 of these end choices. (You don't get 3 because 3 isn't a factor of 4. Explaining why that's important is a little trickier.)