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