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