v

Set v of ZG-generators for the submodule '

(-1+x)e_a

(-1+y)e_b

(-1+xy)e_c

(-1-y-xy-y²-xy²-y³-xy³-y⁴-xy⁴-y⁵-xy⁵-y⁶-xy⁶-y⁷)e_a +(-1-x)e_b +(1+x+yx+xyx+y²x+xy²x+y³x+xy³x+y⁴x+xy⁴x+y⁵x+xy⁵x+y⁶x+xy⁶x)e_c