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