-a^{c1,a0}_{c0,c2} b^{a1}_{v0} c^{c2}_{a2} eta1^{a2}_{a1} a+(c0) a+(v0) a-(a0) a-(c1)
+a^{c1,a1}_{c0,c2} b^{a0}_{v0} c^{c2}_{a2} eta1^{a2}_{a1} a+(c0) a+(v0) a-(a0) a-(c1)