1/8 a^{c2,c3}_{c0,c1} b^{a2,a3}_{a0,a1} c^{c4}_{a4} lambda2^{a1,a4}_{a2,a3} a+(c0) a+(c1) a+(a0) a-(c4) a-(c3) a-(c2)
+1/4 a^{c1,c2}_{c0,c3} b^{a2,a3}_{a0,a1} c^{c3}_{a4} eta1^{a4}_{a3} a+(c0) a+(a0) a+(a1) a-(a2) a-(c2) a-(c1)
-1/4 a^{c1,c2}_{c0,c3} b^{a2,a3}_{a0,a1} c^{c3}_{a4} lambda2^{a1,a4}_{a2,a3} a+(c0) a+(a0) a-(c2) a-(c1)