1/4 a^{}_{} b^{v0,v1}_{a0,a1} c^{c0,a2}_{v0,v1} a+(a0) a+(a1) a-(a2) a-(c0)
+1/2 a^{}_{} b^{v0,v1}_{a0,a1} c^{c0,a2}_{v0,v1} gamma1^{a1}_{a2} a+(a0) a-(c0)
-a^{}_{} b^{v0,v2}_{a0,a1} c^{c0,a2}_{v1,v2} gamma1^{a1}_{a2} a+(a0) a+(v1) a-(v0) a-(c0)