From 50034e14166dccaed097928363667451a3829d17 Mon Sep 17 00:00:00 2001 From: dan Date: Mon, 20 Dec 2021 16:07:18 +0100 Subject: [PATCH 1/2] Start to correct the binomials. --- docs/src/Rings/integer.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/docs/src/Rings/integer.md b/docs/src/Rings/integer.md index f61143e91a52..159f4ce7a0bf 100644 --- a/docs/src/Rings/integer.md +++ b/docs/src/Rings/integer.md @@ -551,8 +551,8 @@ bell(ZZ(20)) * `binomial(n::fmpz, k::fmpz) -> fmpz` -Returns the binomial coefficient ``\frac{n!}{k!(n - k)!}``. If ``n, k < 0`` or -``k > n`` we return zero. +Returns the binomial coefficient ``\frac{n (n-1) \cdots (n-k+1)}{k!}`` for +``k \ge 0`` and returns `0` for `k < 0`. !!! note Julia already defines the `binomial` function for `Int`, which throws an From 50d05ab339ed58a7c1d62cdfd867592e0677ddfd Mon Sep 17 00:00:00 2001 From: dan Date: Mon, 20 Dec 2021 16:09:44 +0100 Subject: [PATCH 2/2] remove the dodgy tests --- test/Rings/integer-test.jl | 2 -- 1 file changed, 2 deletions(-) diff --git a/test/Rings/integer-test.jl b/test/Rings/integer-test.jl index 1a17c1727b3c..5a154ebe9cc6 100644 --- a/test/Rings/integer-test.jl +++ b/test/Rings/integer-test.jl @@ -621,8 +621,6 @@ end @test binomial(ZZ(1), ZZ(0)) == 1 @test binomial(ZZ(1), ZZ(1)) == 1 - @test binomial(ZZ(-3), ZZ(2)) == 0 - @test binomial(ZZ(-3), ZZ(0)) == 0 @test binomial(ZZ(2), ZZ(-3)) == 0 @test binomial(ZZ(0), ZZ(-3)) == 0 @test binomial(ZZ(-1), ZZ(-1)) == 0