These Thurston maps are NET maps for every choice of translation term. They are primitive and have degree 18. PURE MODULAR GROUP HURWITZ EQUIVALENCE CLASSES FOR TRANSLATIONS {0} {lambda1} {lambda2} {lambda1+lambda2} These pure modular group Hurwitz classes each contain only finitely many Thurston equivalence classes. However, this modular group Hurwitz class contains infinitely many Thurston equivalence classes. The number of pure modular group Hurwitz classes in this modular group Hurwitz class is 24. ALL THURSTON MULTIPLIERS c/d IN UNREDUCED FORM 0/3, 0/6, 1/6, 1/3, 2/3, 3/3 Every NET map in these pure modular group Hurwitz classes is rational because every loop multiplier in the mod 2 slope correspondence graph is less than 1. EXCLUDED INTERVALS FOR THE HALF-SPACE COMPUTATION (-116.935245,-1.000000 ) ( -1.000000,-0.015383 ) ( 0.015063,119.667296) SLOPE FUNCTION INFORMATION NUMBER OF FIXED POINTS: 1 EQUATOR? FIXED POINT c d 0 lambda1 lambda2 lambda1+lambda2 1/0 1 3 No No No No NUMBER OF EQUATORS: 0 0 0 0 There are no more slope function fixed points. Number of excluded intervals computed by the fixed point finder: 2543 There are no equators because both elementary divisors are greater than 1. No nontrivial cycles were found. The slope function maps some slope to the nonslope. The slope function orbit of every slope p/q with |p| <= 50 and |q| <= 50 ends in either one of the above cycles or the nonslope. If the slope function maps slope p/q to slope p'/q', then |p'| <= |p| for every slope p/q with |p| <= 50 and |q| <= 50. If the slope function maps slope p/q to slope p'/q', then |q'| <= |q| for every slope p/q with |p| <= 50 and |q| <= 50. FUNDAMENTAL GROUP WREATH RECURSIONS When the translation term of the affine map is 0: NewSphereMachine( "a=(2,6)(3,17)(4,16)(5,9)(7,13)(8,12)(11,15)(14,18)", "b=(1,16)(2,3)(4,13)(5,6)(7,10)(8,9)(11,12)(14,15)(17,18)", "c=<1,1,c^-1,c,c^-1,c^-1,1,1,c^-1,1,1,c,1,1,c,1,1,c>(1,2)(3,18)(4,5)(6,15)(7,8)(9,12)(10,11)(13,14)(16,17)", "d=(1,17)(2,4)(5,7)(6,18)(8,10)(9,15)(11,13)(14,16)", "a*b*c*d"); When the translation term of the affine map is lambda1: NewSphereMachine( "a=(1,4)(2,6)(3,17)(5,9)(7,16)(8,12)(10,13)(11,15)(14,18)", "b=(2,3)(4,16)(5,6)(7,13)(8,9)(11,12)(14,15)(17,18)", "c=<1,d,1,c,c^-1,c^-1,1,1,c^-1,1,1,1,1,1,c,1,1,c>(1,2)(4,5)(6,18)(7,8)(9,15)(10,11)(13,14)(16,17)", "d=(1,17)(2,4)(3,6)(5,7)(8,10)(9,18)(11,13)(12,15)(14,16)", "a*b*c*d"); When the translation term of the affine map is lambda2: NewSphereMachine( "a=<1,c^-1,c^-1,1,1,c^-1,1,1,1,1,1,c,1,1,c,c*d,1,1>(1,5)(2,16)(3,15)(4,8)(6,12)(7,11)(10,14)(13,17)", "b=<1,1,c^-1,c,c^-1,c^-1,1,1,c^-1,1,1,c,1,1,c,1,1,c>(1,2)(3,18)(4,5)(6,15)(7,8)(9,12)(10,11)(13,14)(16,17)", "c=(1,16)(2,3)(4,13)(5,6)(7,10)(8,9)(11,12)(14,15)(17,18)", "d=(1,13)(2,18)(3,5)(4,10)(6,8)(9,11)(12,14)(15,17)", "a*b*c*d"); When the translation term of the affine map is lambda1+lambda2: NewSphereMachine( "a=<1,c^-1,c^-1,1,1,c^-1,1,1,c^-1,1,1,c,1,1,c,c,1,c>(1,5)(2,16)(3,18)(4,8)(6,15)(7,11)(9,12)(10,14)(13,17)", "b=<1,d,1,c,c^-1,c^-1,1,1,c^-1,1,1,1,1,1,c,1,1,c>(1,2)(4,5)(6,18)(7,8)(9,15)(10,11)(13,14)(16,17)", "c=(2,3)(4,16)(5,6)(7,13)(8,9)(11,12)(14,15)(17,18)", "d=(1,16)(2,18)(3,5)(4,13)(6,8)(7,10)(9,11)(12,14)(15,17)", "a*b*c*d");