For any integer N, the sum of all numbers having this property from 1 to N must be a perfect square.  
For any integer N, the sum of all numbers having this property from 1 to N must be a perfect square.  It has been proven that for all numbers less than ten to the three hundredth power, there are no perfect numbers with this property. The tangent and sine functions both have this property, which applies to any function for which f of x plus f of negative x equals zero, and is therefore symmetric about the origin. Every binary number with this property must end in 1, and all prime numbers but the smallest have this property. For 10 points, identify this class of numbers, which leave a remainder when divided by two.
For any integer N, the sum of all numbers having this property from 1 to N must be a perfect square.  
odd numbers