-1/4 a^{v0,v1}_{a0,a3} b^{a4,v2}_{a1,a2} c^{c0}_{v2} gamma1^{a3}_{a4} a+(a0) a+(a1) a+(a2) a-(v1) a-(v0) a-(c0)
+1/2 a^{v0,v2}_{a0,a3} b^{a4,v1}_{a1,a2} c^{c0}_{v2} gamma1^{a3}_{a4} a+(a0) a+(a1) a+(a2) a-(v1) a-(v0) a-(c0)