1/4 a^{}_{a0,a3,v0,v1} b^{a1,a2,a4}_{} gamma1^{a3}_{a4} a+(a0) a+(v0) a+(v1) a-(a2) a-(a1)
+1/4 a^{}_{a1,a2,v0,v1} b^{a0,a3,a4}_{} gamma1^{a2}_{a4} gamma1^{a1}_{a3} a+(v0) a+(v1) a-(a0)
+1/8 a^{}_{a1,a2,v0,v1} b^{a0,a3,a4}_{} lambda2^{a1,a2}_{a3,a4} a+(v0) a+(v1) a-(a0)