Relationships among the Wigner 9j Symbols
Song-Myong Jang · Journal of Mathematical Physics · 1968
Several identities satisfied by the 9j symbols or by the product of 6j and 9j symbols are derived by means of the symmetry properties of the Möbius strip type 15j symbol; in particular, the identity {adgbehcfi}{ajmbknclp}= ∑ xyz (2x+1)(2y+1)(2z+1){adgxjm}{behykn}{cfizlp}{xdmyenzfp}{xjgykhzli}. The resulting recursion relations for the 9j symbols are also considered.