-1/8 a^{a1}_{c0} b^{c1,c2}_{v0,v1} c^{a0,a4}_{a2,a3} lambda2^{a2,a3}_{a1,a4} a+(c0) a+(v0) a+(v1) a-(a0) a-(c2) a-(c1)
+1/4 a^{a1}_{c1} b^{c0,c1}_{v0,v1} c^{a0,a4}_{a2,a3} lambda2^{a2,a3}_{a1,a4} a+(v0) a+(v1) a-(a0) a-(c0)
+1/4 a^{a3}_{c1} b^{c0,c1}_{v0,v1} c^{a1,a2}_{a0,a4} eta1^{a4}_{a3} a+(a0) a+(v0) a+(v1) a-(a2) a-(a1) a-(c0)