Calculation of coefficients of transformations between three-particle hyperspherical harmonics
Description
New versions of the program to calculate the three-particle hyperspherical $\langle l_1'l_2'|l_1 l_2\rangle^\varphi_{KL}$ brackets are presented. Whereas the previous program, Efros (2020), computes the sets of brackets existing at given l_1, l_2, K, and L values, one of the present programs produces the set of all the brackets existing at L values in a range from L_min up to L_max and all K values of a given parity up to some K_max. The other of the present programs provides the sets of all the brackets existing at given l_1, l_2, L values, and all K values of a given parity up to some K_max. Use of such sets of brackets is more convenient. The present programs are considerably faster than the previous one, and they are also easier to follow. As the previous program, the present programs are easy to implement and are well applicable up to very high values of hypermomentum and orbital momenta.