We have this https://shelah.logic.at/papers/506/ definition of $\lim \inf_I \bar{\lambda}$ in 1.1(3): for $I$ a filter on $\kappa$ let $I^+=2^\kappa \setminus I$. $$\lim \inf_I \bar{\lambda}=\min\{\mu:\{i<\kappa:\lambda_i\leq\mu\}\in I^+\}.$$ But then always $\lim \inf_I \bar{\lambda}=0$, since $\emptyset\notin I$, so $\emptyset\in I^+$. Where is the typo in this definition? What is the correct, intended form of it?
2026-03-28 05:21:48.1774675308
Filter, dual ideal,definition of $\liminf_I \lambda$
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