From ff1b012b41867a453de076301b2a0b814cb5dffb Mon Sep 17 00:00:00 2001 From: Luke Naylor <l.naylor@sms.ed.ac.uk> Date: Fri, 12 May 2023 18:22:40 +0100 Subject: [PATCH] Rearrange and correct work from last 4 commits --- main.tex | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/main.tex b/main.tex index 93741a6..70ab47f 100644 --- a/main.tex +++ b/main.tex @@ -807,22 +807,25 @@ beta_value_expr = (beta == a/n) \noindent That is, $r \equiv -a^{-1}b$ mod $n$ ($a$ is coprime to $n$, and so invertible mod $n$). + Substituting the current values of $q$ and $\beta$ into the condition for the radius of the pseudo-wall being positive (eqn \ref{eqn:positive_rad_d_bound_betamin}) we get: \begin{equation} - \frac{1}{\lcm(m,2n^2)}\ZZ +\label{eqn:positive_rad_condition_in_terms_of_q_beta} + \frac{1}{m}\ZZ \ni \sage{positive_radius_condition.subs([q_value_expr,beta_value_expr]).factor()} \in \frac{1}{2n^2}\ZZ \end{equation} -For each $r$, the smallest element of $\frac{1}{\lcm(m,2n^2)}\ZZ$ strictly larger -than the lower bound here is exactly $\frac{1}{\lcm(m,2n^2)}$ greater. -Therefore, if any of the two upper bounds come to within -$\frac{1}{\lcm(m,2n^2)}$ of this lower bound, then there are no solutions for $d$. +\noindent +Both $d$ and the lower bound are elements of $\frac{1}{\lcm(m,2n^2)}\ZZ$. +So, if any of the two upper bounds on $d$ come to within +$\frac{1}{\lcm(m,2n^2)}$ of this lower bound, then there are no solutions for +$d$. Considering equations \ref{eqn:bgmlv2_d_bound_betamin}, @@ -835,9 +838,11 @@ this happens when: \sage{bgmlv2_d_upperbound_exp_term}, \sage{bgmlv3_d_upperbound_exp_term_alt.subs(chbv==0)}, \right) - < \frac{1}{\lcm(m,2n^2)} + < \epsilon := \frac{1}{\lcm(m,2n^2)} \end{equation} +%% refinements using specific values of q and beta + \begin{sagesilent} rhs_numerator = ( positive_radius_condition @@ -849,7 +854,8 @@ rhs_numerator = ( \end{sagesilent} \noindent -Considering the numerator of the right-hand-side: +Considering the numerator of the right-hand-side of +(eqn \ref{eqn:positive_rad_condition_in_terms_of_q_beta}): \begin{align} \sage{rhs_numerator} @@ -858,7 +864,9 @@ Considering the numerator of the right-hand-side: &\equiv ab &\mod n \end{align} -And so, we also have $a(ar+2b) \equiv ab$ (mod $\lcm(m,2n^2)$). +\noindent +And so, we also have $a(ar+2b) \equiv ab$ (mod $2n^2$). + \minorheading{Irrational $\beta$} -- GitLab