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