t = sum_(i=1..7) g_i(t)^9,  g_i(t) = c_i0 + c_i1 t + ... (centre values to 25 digits; '*' = exact fixed value)
g_1:  c_10 = (0.68) + (0) i *;   c_11 = (0.2377286417722771727264126) + (-0.2364362565589428462019184) i  ;   c_12 = (0.4387797567446636116095628) + (0.481569362117117402135128) i  
g_2:  c_20 = (-0.3785547621193369977177295) + (-0.5645651602520381335139526) i  ;   c_21 = (-0.07) + (-0.31) i *;   c_22 = (-0.03967734994998926316271759) + (0.4679292815898705103577492) i  
g_3:  c_30 = (-0.2262493532831990598586424) + (0.673363682032405296579032) i  ;   c_31 = (-0.4953524943459717492668896) + (-0.3238985898461109332779785) i  ;   c_32 = (-0.4349972537548773115790945) + (0.3118667063218101546462722) i  
g_4:  c_40 = (0.2937050872671367462050875) + (-0.672641927365953603046213) i  ;   c_41 = (-0.4789754828157196401582221) + (-0.1373528312129101586405486) i  ;   c_42 = (0.1379057997734994046517114) + (-0.341217610375681523141335) i  
g_5:  c_50 = (-0.008875700374526263118243178) + (0.08596789527248996665389956) i  ;   c_51 = (0.08104885883369187586001388) + (0.00955540624748777808925919) i  ;   c_52 = (-0.4284275482869059704921822) + (-0.5583548133757661307272136) i  
g_6:  c_60 = (-0.6239966706584085503067820) + (0.04337338927561008166789217) i  ;   c_61 = (0.4543271280898496224669652) + (0.1161695022052768493837237) i  ;   c_62 = (0.370925292514416632131622) + (0.2705608219062170725357534) i  
g_7:  c_70 = (0.4903093575181581653392348) + (0.1270491010697389128252679) i  ;   c_71 = (-0.1743585510300795588674816) + (0.2925517081306983491575792) i  ;   c_72 = (-0.05842178786361160581074821) + (0.6744478962753567821251015) i  
homogeneous form: x*y^17 = sum_i G_i(x,y)^9,  G_i = sum_j c_ij x^j y^(2-j)
coefficients of sum g_i^k - t at the centre (exact, shown as floats):
  1.4e-61, 1.8e-60, 2.4e-60, 7.0e-60, 8.6e-60, 5.4e-60, 1.8e-59, 1.5e-59, 2.7e-59, 1.9e-59, 1.7e-59, 1.4e-59, 7.6e-60, 6.4e-60, 2.0e-60, 3.9e-60, 8.9e-61, 8.6e-61, 1.7e-61
