-a^{c0,a2}_{c4,a0} b^{c1}_{a1} c^{c3,c4}_{c2,a3} eta1^{a3}_{a2} a+(c2) a+(a0) a+(a1) a-(c3) a-(c1) a-(c0)
-1/2 a^{c0,a2}_{c4,a0} b^{c4}_{a1} c^{c2,c3}_{c1,a3} eta1^{a3}_{a2} a+(c1) a+(a0) a+(a1) a-(c3) a-(c2) a-(c0)
+a^{c0,a2}_{c4,a0} b^{c1}_{a3} c^{c3,c4}_{c2,a1} eta1^{a3}_{a2} a+(c2) a+(a0) a+(a1) a-(c3) a-(c1) a-(c0)
+1/2 a^{c0,a2}_{c4,a0} b^{c4}_{a3} c^{c2,c3}_{c1,a1} eta1^{a3}_{a2} a+(c1) a+(a0) a+(a1) a-(c3) a-(c2) a-(c0)