-1/2 a^{c0,c1}_{a0,v0} b^{a1,v1}_{c2,c3} c^{c3}_{a2} eta1^{a2}_{a1} a+(c2) a+(a0) a+(v0) a-(v1) a-(c1) a-(c0)
-1/2 a^{c0,c1}_{a1,v0} b^{a2,v1}_{c2,c3} c^{c3}_{a0} gamma1^{a1}_{a2} a+(c2) a+(a0) a+(v0) a-(v1) a-(c1) a-(c0)