# delta system lemma

If $S$ is a set of finite sets^{} such that $|S|={\mathrm{\aleph}}_{1}$ then there is a ${S}^{\prime}\subseteq S$ such that $|{S}^{\prime}|={\mathrm{\aleph}}_{1}$ and $S$ is a http://planetmath.org/node/DeltaSystem$\mathrm{\Delta}$-system.

Title | delta system lemma |
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Canonical name | DeltaSystemLemma |

Date of creation | 2013-03-22 12:55:00 |

Last modified on | 2013-03-22 12:55:00 |

Owner | Henry (455) |

Last modified by | Henry (455) |

Numerical id | 6 |

Author | Henry (455) |

Entry type | Theorem |

Classification | msc 03E99 |

Related topic | DeltaSystem |