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