From the introduction:
This ebook is a bit of a departure for me. The material is mathematical, but it need not be performed with playing cards. It can be performed with pencil and paper close-up, or with a blackboard or a dry-erase white board in platform or stage settings. Thus it can be employed in situations when the use of playing cards would be inappropriate. However, I will describe these effects with playing cards as that is how I use them.
The basic idea is that the performer predicts the sum of a seemingly random array of cards or numbers. The spectator has quite a bit of control over the proceedings but the performer can either glean sufficient information or exert a bit of control in another variation to be aware of the outcome beforehand. The layout and the procedure used to determine numbers in the triangular layout lend themselves to various exotic presentations: "pyramid power," numerology, religious symbolism, or what have you. Each performer will have his or her own ideas of how to use this material. So I leave the presentation to the individual.
The inspiration for these effects is an effect in Harry Lorayne's wonderful book Deck-Sterity (1967) which is now available here at Lybrary.com. Harry's item, in turn was inspired by an idea shown to him by the late T. A. Waters. Both of these gentlemen have my gratitude. As you will see, I have taken the basic concept and spun it in a different direction.
1st edition 2015, 10 pages.
word count: 3419 which is equivalent to 13 standard pages of text