-1/4 a^{a0}_{c0,c1} b^{c3,c4}_{c2,a1} eta1^{a1}_{a0} a+(c0) a+(c1) a+(c2) a-(c4) a-(c3)
-a^{a0}_{c0,c3} b^{c2,c3}_{c1,a1} a+(c0) a+(c1) a+(a1) a-(a0) a-(c2)
+a^{a0}_{c0,c3} b^{c2,c3}_{c1,a1} eta1^{a1}_{a0} a+(c0) a+(c1) a-(c2)
+1/2 a^{a0}_{c1,c2} b^{c1,c2}_{c0,a1} a+(c0) a+(a1) a-(a0)
-1/2 a^{a0}_{c1,c2} b^{c1,c2}_{c0,a1} eta1^{a1}_{a0} a+(c0)