-a^{}_{c0,a0,a2} b^{c2,a3}_{c1,a1} gamma1^{a2}_{a3} a+(c0) a+(c1) a+(a0) a+(a1) a-(c2)
-1/2 a^{}_{c1,a0,a1} b^{c1,a3}_{c0,a2} a+(c0) a+(a0) a+(a1) a+(a2) a-(a3)
+a^{}_{c1,a0,a2} b^{c1,a3}_{c0,a1} gamma1^{a2}_{a3} a+(c0) a+(a0) a+(a1)