and $\langle r_{ee} \rangle$ mean the electron-nucleus and electron-electron distances, respectively. The total energies obtained with these 60-term wave functions are: $E$ = -7.47805 86794 4751 $a.u.$ (Li atom), $E$ = -14.32475 2251 4351 $a.u.$ (Be$^{+}$ ion) and $E$ = -23.42457 46190 439 $a.u.$ (B$^{2+}$ ion), respectively.

The expectation values of the electron-nucleus and electron-electron delta-functions, i.e. $\langle \delta_{eN} \rangle$ and $\langle \delta_{ee} 
\rangle$ are of great interest in various applications. Therefore, it is important to be sure that these values have been determined correctly. For atomic and molecular systems with the Coulomb interaction between each pair of particles there is a very effective test which can be used to estimate the actual accuracy of the expectation values of all two-particle delta-functions $\langle \delta({\bf r}_{ij}) \rangle$. This test is based on accurate numerical evaluation of the electron-nucleus and elecron-electron cusp values. In general, the cusp value between two point particles $a$ and $b$ with electrical charges $q_a$ and $q_b$ and masses $m_a$ and $m_b$ (in atomic units) is: $$\begin{aligned}
  \overline{\nu}_{ab} = q_a q_b \frac{m_a m_b}{m_a + m_b} \label{cuspe}\end{aligned}$$ This is the expected (or ‘classical’) numerical value of the cusp between the electrically charged particles $a$ and $b$. In general, the 