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