a^{c0}_{v0} b^{c2,a1}_{c1,c4} c^{c3,c4}_{a0,a2} eta1^{a2}_{a1} a+(c1) a+(a0) a+(v0) a-(c3) a-(c2) a-(c0)
+1/4 a^{c0}_{v0} b^{c1,a0}_{c2,c3} c^{c2,c3}_{a1,a2} a+(a1) a+(a2) a+(v0) a-(a0) a-(c1) a-(c0)
+1/2 a^{c0}_{v0} b^{c1,a1}_{c2,c3} c^{c2,c3}_{a0,a2} eta1^{a2}_{a1} a+(a0) a+(v0) a-(c1) a-(c0)