1/2 a^{c0,a1}_{a0,v0} b^{a4,v1}_{a2,a3} c^{}_{} lambda2^{a2,a3}_{a1,a4} a+(a0) a+(v0) a-(v1) a-(c0)
-a^{c0,a2}_{a1,v0} b^{a4,v1}_{a0,a3} c^{}_{} eta1^{a3}_{a2} gamma1^{a1}_{a4} a+(a0) a+(v0) a-(v1) a-(c0)
-a^{c0,a2}_{a1,v0} b^{a4,v1}_{a0,a3} c^{}_{} lambda2^{a1,a3}_{a2,a4} a+(a0) a+(v0) a-(v1) a-(c0)