1/2 a^{v0,v1}_{c0,a2} b^{a0}_{v1} c^{a1,a3}_{c1,c2} gamma1^{a2}_{a3} a+(c0) a+(c1) a+(c2) a-(v0) a-(a1) a-(a0)
+1/4 a^{v0,v1}_{c0,a2} b^{a3}_{v1} c^{a0,a1}_{c1,c2} gamma1^{a2}_{a3} a+(c0) a+(c1) a+(c2) a-(v0) a-(a1) a-(a0)