“NielsenSchreierTheorem”的概念、定义、习题解题方法及翻译-数学辞典

单词	NielsenSchreierTheorem
释义	Nielsen-Schreier theorem Every subgroup (http://planetmath.org/Subgroup) of a free group is free. This theorem is named after Jakob Nielsen, who in 1921 proved that every subgroup of a free group of finite rank (http://planetmath.org/FreeGroup) is free, and Otto Schreier, who proved the full result in 1927.
随便看	Sierpinski space Sierpiński conjecture Sierpiński gasket Sierpiński set of Euclidean plane SieveOfEratosthenes sieve of Eratosthenes sieve of Eratosthenes SieveOfEratosthenes1 sigmaalgebra sigmaalgebra1 sigmaalgebraAtAStoppingTime sigmaalgebraGeneratedByARandomVariable sigmacompact SigmaDeltaConstant sigma, delta constant SigmaDerivation sigma derivation sigmafinite sigmaFunction SigmaringOfSets sigma–ring of sets Signature signature SignatureOfAPermutation signature of a permutation

数学辞典收录了18232条数学词条，基本涵盖了常用数学知识及数学英语单词词组的翻译及用法，是数学学习的有利工具。

Nielsen-Schreier theorem