-1/2 a^{c0}_{a0} b^{a1,a2}_{v0,v1} c^{v2}_{a3} eta1^{a3}_{a2} gamma1^{a0}_{a1} a+(v0) a+(v1) a-(v2) a-(c0)
+1/4 a^{c0}_{a0} b^{a1,a2}_{v0,v1} c^{v2}_{a3} lambda2^{a0,a3}_{a1,a2} a+(v0) a+(v1) a-(v2) a-(c0)