1/2 a^{a0}_{v0} b^{a3,v1}_{a1,a2} c^{v3}_{v2} lambda2^{a1,a2}_{a0,a3} a+(v0) a+(v2) a-(v3) a-(v1)
+1/2 a^{a0}_{v0} b^{a3,v2}_{a1,a2} c^{v1}_{v2} lambda2^{a1,a2}_{a0,a3} a+(v0) a-(v1)
+a^{a2}_{v0} b^{a1,v2}_{a0,a3} c^{v1}_{v2} eta1^{a3}_{a2} a+(a0) a+(v0) a-(v1) a-(a1)