1/2 a^{a0,a1}_{c3,v0} b^{c1,c3}_{c0,a2} c^{a3}_{c2} gamma1^{a2}_{a3} a+(c0) a+(c2) a+(v0) a-(a1) a-(a0) a-(c1)
+a^{a0,a2}_{c3,v0} b^{c1,c3}_{c0,a3} c^{a1}_{c2} eta1^{a3}_{a2} a+(c0) a+(c2) a+(v0) a-(a1) a-(a0) a-(c1)