  The symmetric numerical semigroups S(F_a,F_b,F_c) and S(L_k,L_m,L_n)
generated by three Fibonacci (F_a,F_b,F_c) and Lucas (L_k,L_m,L_n) numbers are
considered. Based on divisibility properties of the Fibonacci and Lucas numbers
we establish necessary and sufficient conditions for both semigroups to be
symmetric and calculate their Hilbert generating series, Frobenius numbers and
genera.
