Trachtenberg by Kieron Johnson and Mark Traversoni

Trachtenberg is a modular 3 phase routine which can last 2-20 minutes, builds to a climax which is engaging and entertaining.

Within minutes you will be looking like a maths genius and the great thing is the audience can do the maths for you so you don't even have to add anything up yourself.

The routine explained below is how Kieron and Mark do this, but you can mix it and change it around as you wish, including the back story or not.

You start by showing the book and explain you want to show them something amazing invented by a Russian called Jakow Trachtenberg.

A summary of his life is at the start of the book and you embellish this as much as you like with the true story of his life on the run and imprisonment in prisoner of war camps. In brief Trachtenberg's  imprisonment was so horrific he went into his mind and developed the Trachtenberg Speed Maths System.

Don't worry you don't have to learn Trachtenberg's system, this is all a back story to the effects that follow which are not Trachtenberg's.

Phase 1 You ask someone to write down a number unseen by you from 20 -100 and go on to explain how maths can enable you to do amazing things. You then ask someone if they know the day they were born or if someone would like to know the day they were born.

You proceed by following the books instructions to easily calculate the day. This always gets a great reaction as it's hard to believe such a simple process will produce the end result which can be easily verified using a mobile phones calendar function.

Phase 2 Is more even more interesting as you talk about the concept of speed maths and how Trachtenberg could add up large numbers very quickly. You ask someone or the whole audience to takeout their phones and a truly random (not forced) set of 2 digit numbers is produced using the book. The spectator is asked to add up the numbers but before they get close you have the answer. This is repeated again but with 4 digit numbers with the same effect to the amazement of the audience as the numbers are truly random and can be performed repeatedly if you wish with a different outcome each time.

Included in the book is an advanced but still easy option to do phase 2 with a blank grid where the audience can call out numbers to make rows of 6 digit numbers which again can be calculated just as quickly.

Phase 3 Probability. Given the information from earlier in phase 1 you tell the audience you should be able to work out their hidden chosen number using probability. Using the book you write numbers down and appear to struggle a little. You show your calculations in the grid and ask if their number is there. It is not so you look puzzled and ask for the number. When they tell you the number you look at the grid and realise that all the rows and every combination, horizontal, vertical, diagonal and more add up to the number bringing the routine to a climatic end.