Do you know this card trick?

[kayvee]

When I was 10 years old (many years ago), my friend's older brother performed this card trick for me. He asked me to divide face down a full deck of cards into multiple piles. I can't remember if it had to be divided into a certain number of piles determined by him or into any number of piles that I wanted.

After I did this, he would tell me what would be the sum of the top card of all the piles combined. And I would turn over the top card of each pile and voila, the sum of those cards would be exactly as he had stated. I don't remember what value the jack, queen or king represented.

I went home and tried to figure out how to do this trick. I practiced for hours every day. A week later I figured it out. I came up with a mathematical formula which gave me the correct answer every time. I went back to my friend's older brother and showed him how figured out the trick. He was impressed but said that he did the trick a different way.

In any case, I have forgotten the trick and how to do it. Does anyone know the name of this trick and how to do it?

Any help is appreciated.

 

[Dustrod]

This isn't the one you're looking for because it's from a newer book but if you're' looking for another really cool mathematical principal that can be used for a similar effect, Mike Powers has a really cool effect in Tesseract where the deck is cut 4 times and the top card of each packet is represents a coincidence/prediction/order (depending on how you want to present it) from a 4 digit mathematical equation.

 

[EndersGame]

The description reminds me of several self-working mathematical tricks that work much like this. Take a look at these:

- "Necromantic Calculation" by Roland Hamblen, as described in Hugard's Encyclopedia of Card Tricks.
- "The Puzzler" by Bob Short, as described in Scarne on Card Tricks (p129).

Here's a detailed description of a similar effect, along with a mathematical explanation of how it works.