I am confused about the core, and could you explain that why the allocation x is block by y? Many thanks.

Example: :7={A,B,C} i.e. |=3 w\" (x) = x1 + x2, u3 (x) = uC (x)=min{x1,x2} - 6" = (1,1), 63 = (10,0), eC = (0,10) . ls x = ((10,10), (1,1), (0,0)) in the core? It is pareto efficient Everyone is (weakly) better than with their endowment It is not in the core, because coalition {B, C} can block it with y = ((1,1)), (5,5), (5,5))