GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
# ACEExample "F27-fel0" : enumeration of cosets of H in G, # where G = F(2,7) = C_29, H = Id, using felsch := 0 strategy. # local F, G, a, b, c, d, e, x, y; # We define F(2,7) on 7 generators F := FreeGroup("a","b","c","d","e", "x", "y"); a := F.1; b := F.2; c := F.3; d := F.4; e := F.5; x := F.6; y := F.7; G := F / [a*b*c^-1, b*c*d^-1, c*d*e^-1, d*e*x^-1, e*x*y^-1, x*y*a^-1, y*a*b^-1]; return ACEfunc( FreeGeneratorsOfFpGroup(G), RelatorsOfFpGroup(G), [] # Generators of identity subgroup (empty list) # Options that don't affect the enumeration : echo, enum := "F(2,7), aka C_29", subg := "Id", # Other options wo := "2M", mess := 25000, felsch);