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