These are the modular exponentiation (ME) operators used in the
text. They are meant to replace the operator c_Umod15() outlined
in Section VI B: The Factorization Circuit. The Figures corresponding
to each ME operator (and version number) are listed below.

- shor_meo_N15_ax.py
  N=15, general a, r=2,4
  This is the operator c_Umod15().
  Fig. 19 with a=4,8
  Fig. 20 with a=8
  
- shor_meo_N21_a2.py
  N=21, a=2, r=6
  u_ver=0: Fig. 25
  u_ver=1: Fig. 28
  u_ver=2: Fig. 30

- shor_meo_N21_a13.py
  N=21, a=13, r=2
  u_ver=0: Fig. 32
  
- shor_meo_N35_a4.py
  N=35, a=4, r=6
  u_ver=0: Fig. 36
  u_ver=1: Fig. 38
  u_ver=2: Fig. 41

- shor_meo_N33_a7.py
  N=33, a=7, r=10
  u_ver=0: Fig. 44
  u_ver=1: Fig. 47
  u_ver=2: fig. 50

- shor_meo_N143_a5.py
  N=142, a=5, r=20
  u_ver=0: Fig. 53, Fig. 54, Fig. 55
  u_ver=1: Fig. 56

- shor_meo_N247_a2.py
  N=247, a=2, r=36
  u_ver=0: Fig. 58, Fig. 59
  u_ver=1: Fig. 60
