-1/2 a^{c1,c2,a1}_{c0} b^{c3}_{a0,a2} eta1^{a2}_{a1} a+(c0) a+(a0) a-(c3) a-(c2) a-(c1)
-1/4 a^{c0,c1,a0}_{c2} b^{c2}_{a1,a2} a+(a1) a+(a2) a-(a0) a-(c1) a-(c0)
+1/2 a^{c0,c1,a1}_{c2} b^{c2}_{a0,a2} eta1^{a2}_{a1} a+(a0) a-(c1) a-(c0)