  NMR longitudinal relaxation rates 1/T1 and Knight shifts K have been measured
for superconducting samples of LaFe1-yCoyAsO1-xFx with y=0.0 and 0.0075 and for
a nonsuperconducting metallic sample with y=0.1, where the x values are always
fixed at 0.11. The temperature (T) dependence the relaxation rates 1/T1 of the
superconducting samples has been found to be markedly different from the
behavior 1/T1 T^(2.5-3.0) reported by many groups in the entire T range
measured (from the temperature immediately below the superconducting transition
temperature Tc down to (0.1-0.2)Tc). The nonexistence of the coherence peak has
also been found. Based on the results of the measurements and other kinds of
existing data, arguments are presented on the superconducting symmetry of the
Fe pnictide systems, where the several points which cannot be easily understood
by existing theories, are pointed out. Results of the measurements on the
nonsuperconducting metallic samples are also presented.
