a^{a0,a1}_{c0,v0} b^{c1,v1}_{c3,a2} c^{c3}_{c2} eta1^{a2}_{a1} a+(c0) a+(c2) a+(v0) a-(v1) a-(a0) a-(c1)
-1/2 a^{a0,a1}_{c1,v0} b^{c1,v1}_{c2,a2} c^{c2}_{c0} a+(c0) a+(a2) a+(v0) a-(v1) a-(a1) a-(a0)
+a^{a0,a1}_{c1,v0} b^{c1,v1}_{c2,a2} c^{c2}_{c0} eta1^{a2}_{a1} a+(c0) a+(v0) a-(v1) a-(a0)
-a^{a0,a1}_{c3,v0} b^{c1,v1}_{c0,a2} c^{c3}_{c2} eta1^{a2}_{a1} a+(c0) a+(c2) a+(v0) a-(v1) a-(a0) a-(c1)
+a^{a0,a1}_{c3,v0} b^{c3,v1}_{c0,a2} c^{c2}_{c1} eta1^{a2}_{a1} a+(c0) a+(c1) a+(v0) a-(v1) a-(a0) a-(c2)