So it is that number plus that number 'shifted' 1 place to left.

So if that number is 121, it would look something like this:

121

+121

So it is \(\text{(hundreds)} + \text{(tens + hundreds)} + \text{(ones + tens)} + \text{(ones)}\), which is the same as Pascal's triangle!

Then just clear up the mess and you get a number. ]]>