-1/2 a^{a0}_{v0} b^{a2,a3}_{c0,a1} c^{v1}_{a4} lambda2^{a1,a4}_{a2,a3} a+(c0) a+(v0) a-(v1) a-(a0)
+a^{a1}_{v0} b^{a0,a3}_{c0,a2} c^{v1}_{a4} eta1^{a4}_{a3} eta1^{a2}_{a1} a+(c0) a+(v0) a-(v1) a-(a0)
+a^{a1}_{v0} b^{a0,a3}_{c0,a2} c^{v1}_{a4} lambda2^{a2,a4}_{a1,a3} a+(c0) a+(v0) a-(v1) a-(a0)