a^{v2}_{a0} b^{c0}_{v0} c^{a1,v1}_{c1,v2} gamma1^{a0}_{a1} a+(c1) a+(v0) a-(v1) a-(c0)
-a^{v2}_{a0} b^{c0}_{v2} c^{a1,v1}_{c1,v0} gamma1^{a0}_{a1} a+(c1) a+(v0) a-(v1) a-(c0)