-1/8 a^{v0,v1}_{a0,a3} b^{c1,c2}_{c0,c3} c^{c3,a4}_{a1,a2} gamma1^{a3}_{a4} a+(c0) a+(a0) a+(a1) a+(a2) a-(v1) a-(v0) a-(c2) a-(c1)