sum for all j of the product (aj-a1)(aj-a2)…(aj-an), skipping aj, is positive for any real ai’s iff n=3 or n=5
A Curious Property of Numbers 3 and 5
sum for all j of the product (aj-a1)(aj-a2)…(aj-an), skipping aj, is positive for any real ai’s iff n=3 or n=5