This is the wave function of a particle trapped inside a Harmonic oscillator potential. This particular model is the representation of the probability density of the particle's position (which is the square of the wavefunction) in the energy state where the principle quantum number (n), Orital quantum number (l), and magnetic quantum number (m) are: n=2, l=1, m=0, which is also known as 2P state. The convention is that the n starts from 1.