-1/4 a^{a0,a1}_{c0,a2} b^{a3,v1}_{c3,v0} c^{c3,v2}_{c1,c2} gamma1^{a2}_{a3} a+(c0) a+(c1) a+(c2) a+(v0) a-(v2) a-(v1) a-(a1) a-(a0)
+1/4 a^{a0,a1}_{c3,a2} b^{a3,v1}_{c0,v0} c^{c3,v2}_{c1,c2} gamma1^{a2}_{a3} a+(c0) a+(c1) a+(c2) a+(v0) a-(v2) a-(v1) a-(a1) a-(a0)