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