Sigma_2_3_7:  (1, 0, 0, 1)
Sigma_2_5_7:  (1, 0, 0, 1)
Sigma_3_4_5:  (1, 0, 0, 1)
Sigma_3_4_7:  (1, 0, 0, 1)
Sigma_3_5_7:  (1, 0, 0, 1)
Sigma_4_5_7:  (1, 0, 0, 1)