1/6 a^{a1,a5}_{a0,v0} b^{}_{a2,a3,a4,a6} eta1^{a6}_{a5} a+(a0) a+(a2) a+(a3) a+(a4) a+(v0) a-(a1)
+1/4 a^{a3,a4}_{a0,v0} b^{}_{a1,a2,a5,a6} eta1^{a6}_{a4} eta1^{a5}_{a3} a+(a0) a+(a1) a+(a2) a+(v0)
+1/8 a^{a3,a4}_{a0,v0} b^{}_{a1,a2,a5,a6} lambda2^{a5,a6}_{a3,a4} a+(a0) a+(a1) a+(a2) a+(v0)
-1/12 a^{a4,a5}_{a3,v0} b^{}_{a0,a1,a2,a6} lambda2^{a3,a6}_{a4,a5} a+(a0) a+(a1) a+(a2) a+(v0)