-1/4 a^{a2,v0}_{a0,a1} b^{a3,v3}_{v1,v2} c^{}_{} lambda2^{a0,a1}_{a2,a3} a+(v1) a+(v2) a-(v3) a-(v0)
-1/2 a^{a2,v2}_{a0,a1} b^{a3,v1}_{v0,v2} c^{}_{} lambda2^{a0,a1}_{a2,a3} a+(v0) a-(v1)
-a^{a1,v2}_{a0,a2} b^{a3,v1}_{v0,v2} c^{}_{} gamma1^{a2}_{a3} a+(a0) a+(v0) a-(v1) a-(a1)