#Octave, 27 23 bytes

@(x,y)sum(z=x:y)^2-z*z'

Creates an anonymous function named ans which accepts two inputs: ans(lower, upper)

Online Demo

Explanation

Creates a row vector from x to y (inclusive) and stores it in z. We then sum all the elements using sum and square it (^2). To compute the sum of the squares, we perform matrix multplication between the row-vector and it's transpose. This will effectively square each element and sum up the result. We then subtract the two.

Octave, 27 23 bytes

@(x,y)sum(z=x:y)^2-z*z'

Creates an anonymous function named ans which accepts two inputs: ans(lower, upper)

Online Demo

Explanation

Creates a row vector from x to y (inclusive) and stores it in z. We then sum all the elements using sum and square it (^2). To compute the sum of the squares, we perform matrix multplication between the row-vector and it's transpose. This will effectively square each element and sum up the result. We then subtract the two.

#Octave, 27 bytes

@(x,y)sum(z=x:y)^2-dot(z,z)

Creates an anonymous function named ans which accepts two inputs: ans(lower, upper)

Online Demo

#Octave, 27 23 bytes

@(x,y)sum(z=x:y)^2-z*z'

Creates an anonymous function named ans which accepts two inputs: ans(lower, upper)

Online Demo

Explanation

Creates a row vector from x to y (inclusive) and stores it in z. We then sum all the elements using sum and square it (^2). To compute the sum of the squares, we perform matrix multplication between the row-vector and it's transpose. This will effectively square each element and sum up the result. We then subtract the two.

#Octave, 27 bytes

@(x,y)sum(z=x:y)^2-dot(z,z)

Creates an anonymous function named ans which accepts two inputs: the lower and upper bounds.

Online Demo

#Octave, 27 bytes

@(x,y)sum(z=x:y)^2-dot(z,z)

Creates an anonymous function named ans which accepts two inputs: ans(lower, upper)

Online Demo