I was working on a keypad one day when i came up with my own math problem that I could not solve!
Keypads are 0-9, I was trying to figure out the least number of digital pins needed using the on/off method rather than the resister/analog method.
I call this method, the and-gate-method.
(Someone probably came up with it already)
To confuse us less, lets say the keypad is A-Z and the numbers are digital pins.
with 1 pin i can have 1 letter
with 2 pins i can have 3 letters
with 3 pins i can have 7 letters
with 4 pins i can have 15 letters!
Confused? Example (3 pins):
The Ultimate Math question you’ve been waiting for!
What is the formula?
X represents digital pins
Y represents letters