1/4 a^{c0,v0}_{a0,a1} b^{c1,c2}_{a3,v0} c^{a4}_{a2} gamma1^{a3}_{a4} a+(a0) a+(a1) a+(a2) a-(c2) a-(c1) a-(c0)
-1/2 a^{c0,v0}_{a0,a3} b^{c1,c2}_{a1,v0} c^{a4}_{a2} gamma1^{a3}_{a4} a+(a0) a+(a1) a+(a2) a-(c2) a-(c1) a-(c0)