1/2 a^{c0,v2}_{a0,a2} b^{a3,v0}_{a1,v2} c^{c3,v1}_{c1,c2} gamma1^{a2}_{a3} a+(c1) a+(c2) a+(a0) a+(a1) a-(v1) a-(v0) a-(c3) a-(c0)