Mathematics is full of magic, sometimes more than we even expected. There appears to be a connection between this math trick and 4 x 4 magic squares. I will be interested to see if anyone can form a 4 x 4 magic square from the information provided by The Science Magician in this post. There are 880 ways to make a 4 x 4 magic square, so it seems like it would still be a lot of work. This same process works on a 3 x 3 square and results in numbers that add up to 15 in every case.
51 is a composite number. 51 = 1 x 51 or 3 x 17. Factors of 51: 1, 3, 17, 51. Prime factorization: 51 = 3 x 17.
51 is never a clue in the FIND THE FACTORS puzzles.