#247C. It has purely coclosed G2-structure


D.<e1,e2,e3,e4,e5,e7,f1,f2,f3,f4,f5,f7,g1,g2,g3,g4,g5,g7,h1,h2,h3,h4,h5,h7> = GradedCommutativeAlgebra(QQ)
N=D.cdg_algebra({})
N.inject_variables()
psie=e1*e2*e4-e1*e5*e7+e2*e3*e7+e3*e4*e5
psif=f1*f2*f4-f1*f5*f7+f2*f3*f7+f3*f4*f5
psig=g1*g2*g4-g1*g5*g7+g2*g3*g7+g3*g4*g5
psih=h1*h2*h4-h1*h5*h7+h2*h3*h7+h3*h4*h5
Cgfe=g1*f2*f3*e4*e5*e7+g1*f2*e3*f4*e5*e7+g1*f2*e3*e4*f5*e7+g1*f2*e3*e4*e5*f7+g1*e2*f3*f4*e5*e7+g1*e2*f3*e4*f5*e7+g1*e2*f3*e4*e5*f7+g1*e2*e3*f4*f5*e7+g1*e2*e3*f4*e5*f7+g1*e2*e3*e4*f5*f7+f1*g2*f3*e4*e5*e7+f1*g2*e3*f4*e5*e7+f1*g2*e3*e4*f5*e7+f1*g2*e3*e4*e5*f7+e1*g2*f3*f4*e5*e7+e1*g2*f3*e4*f5*e7+e1*g2*f3*e4*e5*f7+e1*g2*e3*f4*f5*e7+e1*g2*e3*f4*e5*f7+e1*g2*e3*e4*f5*f7+f1*f2*g3*e4*e5*e7+f1*e2*g3*f4*e5*e7+f1*e2*g3*e4*f5*e7+f1*e2*g3*e4*e5*f7+e1*f2*g3*f4*e5*e7+e1*f2*g3*e4*f5*e7+e1*f2*g3*e4*e5*f7+e1*e2*g3*f4*f5*e7+e1*e2*g3*f4*e5*f7+e1*e2*g3*e4*f5*f7+f1*f2*e3*g4*e5*e7+f1*e2*f3*g4*e5*e7+f1*e2*e3*g4*f5*e7+f1*e2*e3*g4*e5*f7+e1*f2*f3*g4*e5*e7+e1*f2*e3*g4*f5*e7+e1*f2*e3*g4*e5*f7+e1*e2*f3*g4*f5*e7+e1*e2*f3*g4*e5*f7+e1*e2*e3*g4*f5*f7+f1*f2*e3*e4*g5*e7+f1*e2*f3*e4*g5*e7+f1*e2*e3*f4*g5*e7+f1*e2*e3*e4*g5*f7+e1*f2*f3*e4*g5*e7+e1*f2*e3*f4*g5*e7+e1*f2*e3*e4*g5*f7+e1*e2*f3*f4*g5*e7+e1*e2*f3*e4*g5*f7+e1*e2*e3*f4*g5*f7+f1*f2*e3*e4*e5*g7+f1*e2*f3*e4*e5*g7+f1*e2*e3*f4*e5*g7+f1*e2*e3*e4*f5*g7+e1*f2*f3*e4*e5*g7+e1*f2*e3*f4*e5*g7+e1*f2*e3*e4*f5*g7+e1*e2*f3*f4*e5*g7+e1*e2*f3*e4*f5*g7+e1*e2*e3*f4*f5*g7
Cfgh=f1*g2*g3*h4*h5*h7+f1*g2*h3*g4*h5*h7+f1*g2*h3*h4*g5*h7+f1*g2*h3*h4*h5*g7+f1*h2*g3*g4*h5*h7+f1*h2*g3*h4*g5*h7+f1*h2*g3*h4*h5*g7+f1*h2*h3*g4*g5*h7+f1*h2*h3*g4*h5*g7+f1*h2*h3*h4*g5*g7+g1*f2*g3*h4*h5*h7+g1*f2*h3*g4*h5*h7+g1*f2*h3*h4*g5*h7+g1*f2*h3*h4*h5*g7+h1*f2*g3*g4*h5*h7+h1*f2*g3*h4*g5*h7+h1*f2*g3*h4*h5*g7+h1*f2*h3*g4*g5*h7+h1*f2*h3*g4*h5*g7+h1*f2*h3*h4*g5*g7+g1*g2*f3*h4*h5*h7+g1*h2*f3*g4*h5*h7+g1*h2*f3*h4*g5*h7+g1*h2*f3*h4*h5*g7+h1*g2*f3*g4*h5*h7+h1*g2*f3*h4*g5*h7+h1*g2*f3*h4*h5*g7+h1*h2*f3*g4*g5*h7+h1*h2*f3*g4*h5*g7+h1*h2*f3*h4*g5*g7+g1*g2*h3*f4*h5*h7+g1*h2*g3*f4*h5*h7+g1*h2*h3*f4*g5*h7+g1*h2*h3*f4*h5*g7+h1*g2*g3*f4*h5*h7+h1*g2*h3*f4*g5*h7+h1*g2*h3*f4*h5*g7+h1*h2*g3*f4*g5*h7+h1*h2*g3*f4*h5*g7+h1*h2*h3*f4*g5*g7+g1*g2*h3*h4*f5*h7+g1*h2*g3*h4*f5*h7+g1*h2*h3*g4*f5*h7+g1*h2*h3*h4*f5*g7+h1*g2*g3*h4*f5*h7+h1*g2*h3*g4*f5*h7+h1*g2*h3*h4*f5*g7+h1*h2*g3*g4*f5*h7+h1*h2*g3*h4*f5*g7+h1*h2*h3*g4*f5*g7+g1*g2*h3*h4*h5*f7+g1*h2*g3*h4*h5*f7+g1*h2*h3*g4*h5*f7+g1*h2*h3*h4*g5*f7+h1*g2*g3*h4*h5*f7+h1*g2*h3*g4*h5*f7+h1*g2*h3*h4*g5*f7+h1*h2*g3*g4*h5*f7+h1*h2*g3*h4*g5*f7+h1*h2*h3*g4*g5*f7
(-1/6)*psie*Cgfe*psif*psih*Cfgh*psig



D.<e1,e2,e3,e4,e5,e7,f1,f2,f3,f4,f5,f7,g1,g2,g3,g4,g5,g7,h1,h2,h3,h4,h5,h7,x1,x2,x3,x4,x5,x7,y1,y2,y3,y4,y5,y7,z1,z2,z3,z4,z5,z7> = GradedCommutativeAlgebra(QQ)
N=D.cdg_algebra({})
N.inject_variables()
psie=e1*e2*e4-e1*e5*e7+e2*e3*e7+e3*e4*e5
psif=f1*f2*f4-f1*f5*f7+f2*f3*f7+f3*f4*f5
psig=g1*g2*g4-g1*g5*g7+g2*g3*g7+g3*g4*g5
psix=x1*x2*x4-x1*x5*x7+x2*x3*x7+x3*x4*x5
psiy=y1*y2*y4-y1*y5*y7+y2*y3*y7+y3*y4*y5
psiz=z1*z2*z4-z1*z5*z7+z2*z3*z7+z3*z4*z5
psixyz=x1*y2*z4-x1*y5*z7+x2*y3*z7+x3*y4*z5
Chxe=h1*x2*x3*e4*e5*e7+h1*x2*e3*x4*e5*e7+h1*x2*e3*e4*x5*e7+h1*x2*e3*e4*e5*x7+h1*e2*x3*x4*e5*e7+h1*e2*x3*e4*x5*e7+h1*e2*x3*e4*e5*x7+h1*e2*e3*x4*x5*e7+h1*e2*e3*x4*e5*x7+h1*e2*e3*e4*x5*x7+x1*h2*x3*e4*e5*e7+x1*h2*e3*x4*e5*e7+x1*h2*e3*e4*x5*e7+x1*h2*e3*e4*e5*x7+e1*h2*x3*x4*e5*e7+e1*h2*x3*e4*x5*e7+e1*h2*x3*e4*e5*x7+e1*h2*e3*x4*x5*e7+e1*h2*e3*x4*e5*x7+e1*h2*e3*e4*x5*x7+x1*x2*h3*e4*e5*e7+x1*e2*h3*x4*e5*e7+x1*e2*h3*e4*x5*e7+x1*e2*h3*e4*e5*x7+e1*x2*h3*x4*e5*e7+e1*x2*h3*e4*x5*e7+e1*x2*h3*e4*e5*x7+e1*e2*h3*x4*x5*e7+e1*e2*h3*x4*e5*x7+e1*e2*h3*e4*x5*x7+x1*x2*e3*h4*e5*e7+x1*e2*x3*h4*e5*e7+x1*e2*e3*h4*x5*e7+x1*e2*e3*h4*e5*x7+e1*x2*x3*h4*e5*e7+e1*x2*e3*h4*x5*e7+e1*x2*e3*h4*e5*x7+e1*e2*x3*h4*x5*e7+e1*e2*x3*h4*e5*x7+e1*e2*e3*h4*x5*x7+x1*x2*e3*e4*h5*e7+x1*e2*x3*e4*h5*e7+x1*e2*e3*x4*h5*e7+x1*e2*e3*e4*h5*x7+e1*x2*x3*e4*h5*e7+e1*x2*e3*x4*h5*e7+e1*x2*e3*e4*h5*x7+e1*e2*x3*x4*h5*e7+e1*e2*x3*e4*h5*x7+e1*e2*e3*x4*h5*x7+x1*x2*e3*e4*e5*h7+x1*e2*x3*e4*e5*h7+x1*e2*e3*x4*e5*h7+x1*e2*e3*e4*x5*h7+e1*x2*x3*e4*e5*h7+e1*x2*e3*x4*e5*h7+e1*x2*e3*e4*x5*h7+e1*e2*x3*x4*e5*h7+e1*e2*x3*e4*x5*h7+e1*e2*e3*x4*x5*h7
Chyf=h1*y2*y3*f4*f5*f7+h1*y2*f3*y4*f5*f7+h1*y2*f3*f4*y5*f7+h1*y2*f3*f4*f5*y7+h1*f2*y3*y4*f5*f7+h1*f2*y3*f4*y5*f7+h1*f2*y3*f4*f5*y7+h1*f2*f3*y4*y5*f7+h1*f2*f3*y4*f5*y7+h1*f2*f3*f4*y5*y7+y1*h2*y3*f4*f5*f7+y1*h2*f3*y4*f5*f7+y1*h2*f3*f4*y5*f7+y1*h2*f3*f4*f5*y7+f1*h2*y3*y4*f5*f7+f1*h2*y3*f4*y5*f7+f1*h2*y3*f4*f5*y7+f1*h2*f3*y4*y5*f7+f1*h2*f3*y4*f5*y7+f1*h2*f3*f4*y5*y7+y1*y2*h3*f4*f5*f7+y1*f2*h3*y4*f5*f7+y1*f2*h3*f4*y5*f7+y1*f2*h3*f4*f5*y7+f1*y2*h3*y4*f5*f7+f1*y2*h3*f4*y5*f7+f1*y2*h3*f4*f5*y7+f1*f2*h3*y4*y5*f7+f1*f2*h3*y4*f5*y7+f1*f2*h3*f4*y5*y7+y1*y2*f3*h4*f5*f7+y1*f2*y3*h4*f5*f7+y1*f2*f3*h4*y5*f7+y1*f2*f3*h4*f5*y7+f1*y2*y3*h4*f5*f7+f1*y2*f3*h4*y5*f7+f1*y2*f3*h4*f5*y7+f1*f2*y3*h4*y5*f7+f1*f2*y3*h4*f5*y7+f1*f2*f3*h4*y5*y7+y1*y2*f3*f4*h5*f7+y1*f2*y3*f4*h5*f7+y1*f2*f3*y4*h5*f7+y1*f2*f3*f4*h5*y7+f1*y2*y3*f4*h5*f7+f1*y2*f3*y4*h5*f7+f1*y2*f3*f4*h5*y7+f1*f2*y3*y4*h5*f7+f1*f2*y3*f4*h5*y7+f1*f2*f3*y4*h5*y7+y1*y2*f3*f4*f5*h7+y1*f2*y3*f4*f5*h7+y1*f2*f3*y4*f5*h7+y1*f2*f3*f4*y5*h7+f1*y2*y3*f4*f5*h7+f1*y2*f3*y4*f5*h7+f1*y2*f3*f4*y5*h7+f1*f2*y3*y4*f5*h7+f1*f2*y3*f4*y5*h7+f1*f2*f3*y4*y5*h7
Chzg=h1*z2*z3*g4*g5*g7+h1*z2*g3*z4*g5*g7+h1*z2*g3*g4*z5*g7+h1*z2*g3*g4*g5*z7+h1*g2*z3*z4*g5*g7+h1*g2*z3*g4*z5*g7+h1*g2*z3*g4*g5*z7+h1*g2*g3*z4*z5*g7+h1*g2*g3*z4*g5*z7+h1*g2*g3*g4*z5*z7+z1*h2*z3*g4*g5*g7+z1*h2*g3*z4*g5*g7+z1*h2*g3*g4*z5*g7+z1*h2*g3*g4*g5*z7+g1*h2*z3*z4*g5*g7+g1*h2*z3*g4*z5*g7+g1*h2*z3*g4*g5*z7+g1*h2*g3*z4*z5*g7+g1*h2*g3*z4*g5*z7+g1*h2*g3*g4*z5*z7+z1*z2*h3*g4*g5*g7+z1*g2*h3*z4*g5*g7+z1*g2*h3*g4*z5*g7+z1*g2*h3*g4*g5*z7+g1*z2*h3*z4*g5*g7+g1*z2*h3*g4*z5*g7+g1*z2*h3*g4*g5*z7+g1*g2*h3*z4*z5*g7+g1*g2*h3*z4*g5*z7+g1*g2*h3*g4*z5*z7+z1*z2*g3*h4*g5*g7+z1*g2*z3*h4*g5*g7+z1*g2*g3*h4*z5*g7+z1*g2*g3*h4*g5*z7+g1*z2*z3*h4*g5*g7+g1*z2*g3*h4*z5*g7+g1*z2*g3*h4*g5*z7+g1*g2*z3*h4*z5*g7+g1*g2*z3*h4*g5*z7+g1*g2*g3*h4*z5*z7+z1*z2*g3*g4*h5*g7+z1*g2*z3*g4*h5*g7+z1*g2*g3*z4*h5*g7+z1*g2*g3*g4*h5*z7+g1*z2*z3*g4*h5*g7+g1*z2*g3*z4*h5*g7+g1*z2*g3*g4*h5*z7+g1*g2*z3*z4*h5*g7+g1*g2*z3*g4*h5*z7+g1*g2*g3*z4*h5*z7+z1*z2*g3*g4*g5*h7+z1*g2*z3*g4*g5*h7+z1*g2*g3*z4*g5*h7+z1*g2*g3*g4*z5*h7+g1*z2*z3*g4*g5*h7+g1*z2*g3*z4*g5*h7+g1*z2*g3*g4*z5*h7+g1*g2*z3*z4*g5*h7+g1*g2*z3*g4*z5*h7+g1*g2*g3*z4*z5*h7
psie*Chxe*psix*psif*Chyf*psiy*psig*Chzg*psiz*psixyz

#psiplus=c*(x2*x3*x4+x1*x4*x5-x1*x2*x7+x3*x5*x7)


D.<e1,e2,e3,e4,e5,e7,f1,f2,f3,f4,f5,f7,x1,x2,x3,x4,x5,x7> = GradedCommutativeAlgebra(QQ,degrees=(1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2))
N=D.cdg_algebra({})
N.inject_variables()
psie=e1*e2*e4-e1*e5*e7+e2*e3*e7+e3*e4*e5
psif=f1*f2*f4-f1*f5*f7+f2*f3*f7+f3*f4*f5
omegaxf=(x1*f3+x2*f5+x4*f7)-(f1*x3+f2*x5+f4*x7)
Cxfe=x1*f2*f3*e4*e5*e7+x1*f2*e3*f4*e5*e7+x1*f2*e3*e4*f5*e7+x1*f2*e3*e4*e5*f7+x1*e2*f3*f4*e5*e7+x1*e2*f3*e4*f5*e7+x1*e2*f3*e4*e5*f7+x1*e2*e3*f4*f5*e7+x1*e2*e3*f4*e5*f7+x1*e2*e3*e4*f5*f7-x2*f1*f3*e4*e5*e7-x2*f1*e3*f4*e5*e7-x2*f1*e3*e4*f5*e7-x2*f1*e3*e4*e5*f7-x2*e1*f3*f4*e5*e7-x2*e1*f3*e4*f5*e7-x2*e1*f3*e4*e5*f7-x2*e1*e3*f4*f5*e7-x2*e1*e3*f4*e5*f7-x2*e1*e3*e4*f5*f7+x3*f1*f2*e4*e5*e7+x3*f1*e2*f4*e5*e7+x3*f1*e2*e4*f5*e7+x3*f1*e2*e4*e5*f7+x3*e1*f2*f4*e5*e7+x3*e1*f2*e4*f5*e7+x3*e1*f2*e4*e5*f7+x3*e1*e2*f4*f5*e7+x3*e1*e2*f4*e5*f7+x3*e1*e2*e4*f5*f7-x4*f1*f2*e3*e5*e7-x4*f1*e2*f3*e5*e7-x4*f1*e2*e3*f5*e7-x4*f1*e2*e3*e5*f7-x4*e1*f2*f3*e5*e7-x4*e1*f2*e3*f5*e7-x4*e1*f2*e3*e5*f7-x4*e1*e2*f3*f5*e7-x4*e1*e2*f3*e5*f7-x4*e1*e2*e3*f5*f7+x5*f1*f2*e3*e4*e7+x5*f1*e2*f3*e4*e7+x5*f1*e2*e3*f4*e7+x5*f1*e2*e3*e4*f7+x5*e1*f2*f3*e4*e7+x5*e1*f2*e3*f4*e7+x5*e1*f2*e3*e4*f7+x5*e1*e2*f3*f4*e7+x5*e1*e2*f3*e4*f7+x5*e1*e2*e3*f4*f7-x7*f1*f2*e3*e4*e5-x7*f1*e2*f3*e4*e5-x7*f1*e2*e3*f4*e5-x7*f1*e2*e3*e4*f5-x7*e1*f2*f3*e4*e5-x7*e1*f2*e3*f4*e5-x7*e1*f2*e3*e4*f5-x7*e1*e2*f3*f4*e5-x7*e1*e2*f3*e4*f5-x7*e1*e2*e3*f4*f5
1/2*psie*Cxfe*psif*omegaxf

# x1^2 + x2^2 + x3^2 + x4^2 + x5^2 + x7^2
# The metric is positive definite

A.<x1,x2,x3,x4,x5,x6,x7> = GradedCommutativeAlgebra(QQ)
M=A.cdg_algebra({ x4:x1*x2, x5:x1*x3, x6: x1*x4+x3*x5, x7: x1*x5})
M.inject_variables()
omega=x1*x3+x2*x5+x4*x7
psi=x1*x2*x4-x1*x5*x7+x2*x3*x7+x3*x4*x5
psiplus=-(x2*x3*x4+x1*x4*x5-x1*x2*x7+x3*x5*x7)
eta=x4+x6
omega*psi
psi*psiplus-(2/3)*omega^3
psi.differential()
omega*omega.differential()-psi*eta.differential()
omega^2*eta.differential()+2*psiplus*omega.differential()