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