Central elements in the universal enveloping algebra and function of   matrix elements
  In the paper a construction of central elements in $U(\mathfrak{o}_N)$ and $U(\mathfrak{g}_2)$ based on invariant theory is given. New function of matrix elements that appear in description of the center of $U(\mathfrak{g}_2)$ are defined. 
D.V. Artamonov, V.A. Golubeva
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