>147,156,158
　a-b=x, b-c=y, c-a=z とおくと x+y+z =0.
　与式 =x^3 +y^3 +z^3 = 3xyz +(x+y+z)(x^2 +y^2 +z^2 -xy-yz-zx)
　= 3xyz = 3(a-b)(b-c)(c-a).