Thank you for the article! I have enjoyed it
An equivalent way to figure out the value of N is to see the 1802 squares as if they were the elements
of a geometric progression whose first member is a(1)=17 (the square on the botton of the first column) and ratio=2.
The element on the top of the first column would be a(17) and the element on the botton of the second column would be a(18), and so on.
If, for example, we wanted to plot the third square from the botton of the second column the value of N would be:
N = a(20) = 17 x 2^(20-1) = 17 x 2^19 = 8912896
And if we also wanted to plot the top square of the fourth column:
N = a(20) + a(68) = 17 x 2^(20-1) + 17 x 2^(68-1) = 8912896 + 2508757194024499019776 = 2508757194024507932672
In other words, according to its position inside the geometric progression, each square has a value that has to be added to the value of other squares to be plotted together.
The final result for N is the same, but seen from other perspective. :-)