7fed8273b5856afe51ee87e546807273e5b31390b25f8073bac86b5816184f

7fed8273b5856afe51ee87e546837c732f4d76ac772a530cd497b61028f0ac

7fed8273b5856afe51ee87e54583747329de4d6f1bad5e4bbab7db335199

Γ(z) = (z-1)!