-1/2 a^{a0}_{c3} b^{c0}_{a1} c^{c3,a2}_{c1,c2} gamma1^{a1}_{a2} a+(c1) a+(c2) a-(a0) a-(c0)
+1/2 a^{a0}_{c3} b^{c3}_{a1} c^{c2,a2}_{c0,c1} gamma1^{a1}_{a2} a+(c0) a+(c1) a-(a0) a-(c2)
-1/2 a^{a1}_{c3} b^{c0}_{a2} c^{c3,a0}_{c1,c2} eta1^{a2}_{a1} a+(c1) a+(c2) a-(a0) a-(c0)
+1/2 a^{a1}_{c3} b^{c3}_{a2} c^{c2,a0}_{c0,c1} eta1^{a2}_{a1} a+(c0) a+(c1) a-(a0) a-(c2)