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