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