For example
1+15=16
2+14=16
3+13=16
4+12=16
5+11=16
6+10=16
7+9=16
8+8=16
the are all the sums
1*15=15
2*14=28
3*13=39
4*12=48
5*11=55
6*10=60
7*9=63
8*8=64
If the numbers do not repeat the product of 9*7=63 is the maximum product,
If the numbers can be the same the product of 8*8 is the maximum product
