Pedro Pisa Picked A Pack Of Peculiar Numbers, A Pack Of Peculiar Numbers Pedro Pisa Picked

“Fight Against Stupidity And Bureaucracy”


A slightly different Friday post this holiday week. It reads a bit like a tongue-twister, but it’s actually more of a number twister.  

Instead of the usual Friday Factoid for those interested in numbers, how about a magic equation from an unlikely source?

The unlikely source was ‘Scripta Mathematica’, a quarterly journal published by Yeshiva University from 1932 until 1973, and devoted to the philosophy, history, and expository treatment of mathematics. It was said to be, “the only mathematical magazine in the world edited by specialists for laymen.”

Never destined to be a best seller, it did however produce a few interesting tidbits for laypersons interested in, or fascinated by, mathematics or numbers.

One of these was in its March 1955 edition, when it published an article from someone named, Pedro A. Pisa who had picked a pack of peculiar numbers and formed them into a most curious equation.

The equation was simply this,  


123,789  +  561,945  +  642,864  =  242,868  +  323,787  +  761,943


On the face of it there is nothing spectacular here. This just an ordinary looking and fairly simple arithmetic equation.

Ordinary, except for the fact that you could remove many of the terms, from either end of this equation, and it still worked.

For example,

Pedro A. Pisa equation


Ordinary, except you could remove the two center digits from each term, and it still balanced.

For example


1289  +  5645  +  6464  =  2468  +  3287  +  7643


You could even repeat this process and it still worked:


19  +  55  +  64  =  28  +  37  +  73



And ordinary but perhaps most amazing of all, you could square every term above, in every equation, and they will still all remain true.


And it was all figured out by a someone called Pedro A Pisa.