-1/4 a^{a1,v0}_{c0,c1} b^{c3}_{c2} c^{a0,a4}_{a2,a3} lambda2^{a2,a3}_{a1,a4} a+(c0) a+(c1) a+(c2) a-(v0) a-(a0) a-(c3)
+1/2 a^{a1,v0}_{c0,c2} b^{c2}_{c1} c^{a0,a4}_{a2,a3} lambda2^{a2,a3}_{a1,a4} a+(c0) a+(c1) a-(v0) a-(a0)
-1/2 a^{a3,v0}_{c0,c2} b^{c2}_{c1} c^{a1,a2}_{a0,a4} eta1^{a4}_{a3} a+(c0) a+(c1) a+(a0) a-(v0) a-(a2) a-(a1)