A Statement in Combinatorics that is Independent of ZFC
نویسنده
چکیده
There are some statements that are independent of Zermelo-Frankl Set Theory (henceforth ZFC). Such statements cannot be proven or disproven by conventional mathematics. The Continuum Hypothesis is one such statement (“There is no cardinality strictly between א0 and 2א0 .”) Many such statements are unnatural in that they deal with objects only set theorists and other logicians care about. We present a natural statement in combinatorics that is independent of ZFC. The result is due to Erdős. In the last section we will discuss the question of whether the statement is really natural.
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