for h being non constant standard special_circular_sequence holds
( 1 <= i_w_n h & i_w_n h <= len (GoB h) & 1 <= i_e_n h & i_e_n h <= len (GoB h) & 1 <= i_w_s h & i_w_s h <= len (GoB h) & 1 <= i_e_s h & i_e_s h <= len (GoB h) )