  We describe a further development of the stochastic state selection method, a
new Monte Carlo method we have proposed recently to make numerical calculations
in large quantum spin systems. Making recursive use of the stochastic state
selection technique in the Lanczos approach, we estimate the ground state
energy of the spin-1/2 quantum Heisenberg antiferromagnet on a 48-site
triangular lattice. Our result for the upper bound of the ground state energy
is -0.1833 +/- 0.0003 per bond. This value, being compatible with values from
other work, indicates that our method is efficient in calculating energy
eigenvalues of frustrated quantum spin systems on large lattices.
