From 893abbaf05ddf0658d8648a3c6f6535708d2e0de Mon Sep 17 00:00:00 2001 From: Ulli Kehrle Date: Thu, 8 Nov 2018 12:26:01 +0100 Subject: Don't use unicode subscripts in README as some systems don't render it properly. This mostly reverts 407bc6af406de7286d377e5f2d1f848aaa84eb2e. --- README.md | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'README.md') diff --git a/README.md b/README.md index b4523ec..fed4217 100644 --- a/README.md +++ b/README.md @@ -4,12 +4,12 @@ This package provides an algorithm that computes a subgroup ladder from a permut The algorithm was described by Bernd Schmalz in [1, Theorem 3.1.1]. Solutions of some problems in group theory can relatively easy be transferred to a sub- or supergroup if the index is small. -Let G be a permutation group on the set {1,…,n}. -So one might try to find a series of subgroups G = H₀,…,Hₖ = Sₙ of the symmetric group Sₙsuch that Hᵢ₋₁ is a subgroup of Hᵢ for every i and transfer the solution of a problem for the symmetric group step by step to G. +Let G be a permutation group on the set {1,...,n}. +So one might try to find a series of subgroups G = H_0,...,H_k = Sₙ of the symmetric group S_nsuch that H_{i-1} is a subgroup of H_i for every i and transfer the solution of a problem for the symmetric group step by step to G. Sometimes it is not possible to find such a series with small indices between consecutive subgroups. This is where subgroup ladders may make sense: -A subgroup ladder is series of subgroups G = H₀,…,Hₖ = Sₙ of the symmetric group such that for every 1≤i≤k, Hᵢ is a subgroup of Hᵢ₋₁ or Hᵢ₋₁ is a subgroup of Hᵢ. +A subgroup ladder is series of subgroups G = H_0,...,H_k = S_n of the symmetric group such that for every 1<=i<=k, H_i is a subgroup of H_{i-1} or H_{i-1} is a subgroup of H_i. So we sometimes go up to a larger group in order to keep the indices small. If G is a Young subgroup of S_n, the algorithm in this repository can find a subgroup ladder of G such that the indices are at most the degree of the permutation group. -- cgit v1.2.3-24-g4f1b From bfac88769e4788626e3166d7d6f4a3392ac9dbcc Mon Sep 17 00:00:00 2001 From: Ulli Kehrle Date: Thu, 8 Nov 2018 12:48:17 +0100 Subject: README: replace unicode S_n with ascii one. --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'README.md') diff --git a/README.md b/README.md index fed4217..bfe9bec 100644 --- a/README.md +++ b/README.md @@ -5,7 +5,7 @@ The algorithm was described by Bernd Schmalz in [1, Theorem 3.1.1]. Solutions of some problems in group theory can relatively easy be transferred to a sub- or supergroup if the index is small. Let G be a permutation group on the set {1,...,n}. -So one might try to find a series of subgroups G = H_0,...,H_k = Sₙ of the symmetric group S_nsuch that H_{i-1} is a subgroup of H_i for every i and transfer the solution of a problem for the symmetric group step by step to G. +So one might try to find a series of subgroups G = H_0,...,H_k = S_n of the symmetric group S_nsuch that H_{i-1} is a subgroup of H_i for every i and transfer the solution of a problem for the symmetric group step by step to G. Sometimes it is not possible to find such a series with small indices between consecutive subgroups. This is where subgroup ladders may make sense: -- cgit v1.2.3-24-g4f1b From 12c5e8a03fe7db036a2e432079f162317c1c7c68 Mon Sep 17 00:00:00 2001 From: Ulli Kehrle Date: Thu, 8 Nov 2018 13:17:41 +0100 Subject: README: mention how to generate documentation --- README.md | 1 + 1 file changed, 1 insertion(+) (limited to 'README.md') diff --git a/README.md b/README.md index bfe9bec..d898268 100644 --- a/README.md +++ b/README.md @@ -47,6 +47,7 @@ install and use it, resp. where to find out more ## Documentation The documentation of this package is available as [HTML](https://hrnz.li/subgroupladders) and as a [PDF](https://hrnz.li/subgroupladders/manual.pdf). +It can also be generated locally with `gap makedoc.g`. ## Contact -- cgit v1.2.3-24-g4f1b