Coefficient of fractional parentage

The Coefficient of Fractional Parentage (CFP) is a concept used in quantum mechanics and atomic physics, particularly in the context of many-particle systems, such as atoms or nuclei composed of multiple indistinguishable particles (e.g., electrons, protons, neutrons). When dealing with systems of identical particles, the overall wave function must be symmetric (for bosons) or antisymmetric (for fermions) under the exchange of particles.