-1/2 a^{v0}_{a0} b^{a2}_{a1} c^{c0,c1}_{a3,v0} eta1^{a3}_{a2} a+(a0) a+(a1) a-(c1) a-(c0)
+1/2 a^{v0}_{a2} b^{a3}_{a0} c^{c0,c1}_{a1,v0} gamma1^{a2}_{a3} a+(a0) a+(a1) a-(c1) a-(c0)