In this paper, we examine a unique identity—Entry 27 from Ramanujan’s Notebook IV. By leveraging the symmetry properties of integral quadratic forms, we provide natural representations of both sides of the identity in terms of three distinct classes of binary quadratic forms with discriminant −252. The combination of integral quadratic forms and exact covering systems leads to a collection of surprisingly elegant identities.
Zhu Cao (Tue,) studied this question.