Can you arrange the even numbers?
Well cant you arrange numbers any way you want? Least to greatest or whatever you please. There can be an arangement of random numbers chosen to be thrown ing a pattern that makes sence to no one.
Why is it impossible to arrange the numbers 1 to 9 in a sum circle with all the numbers in the boxes being prime?
The proof is easier than you might think. There are 5 odd numbers (1, 3, 5, 7, 9) in the range, but only four even numbers (2, 4, 6, 8). There are not, consequently, enough even numbers to separate all the odd numbers. Two odd numbers must inevitably appear next to each other somewhere in the circle, totalling a non-prime even number. Odd and even numbers must alternate all the way around a sum circle…