update book

doc/LectureNotes/_build/html/week40.html

@@ -62,7 +62,7 @@
     <script>DOCUMENTATION_OPTIONS.pagename = 'week40';</script>
     <link rel="index" title="Index" href="genindex.html" />
     <link rel="search" title="Search" href="search.html" />
-    <link rel="next" title="Project 1 on Machine Learning, deadline October 6 (midnight), 2025" href="project1.html" />
+    <link rel="next" title="Week 41 Neural networks and constructing a neural network code" href="week41.html" />
     <link rel="prev" title="Week 39: Resampling methods and logistic regression" href="week39.html" />
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@@ -236,6 +236,7 @@
 <li class="toctree-l1"><a class="reference internal" href="exercisesweek39.html">Exercises week 39</a></li>
 <li class="toctree-l1"><a class="reference internal" href="week39.html">Week 39: Resampling methods and logistic regression</a></li>
 <li class="toctree-l1 current active"><a class="current reference internal" href="#">Week 40: Gradient descent methods (continued) and start Neural networks</a></li>
+<li class="toctree-l1"><a class="reference internal" href="week41.html">Week 41 Neural networks and constructing a neural network code</a></li>
 </ul>
 <p aria-level="2" class="caption" role="heading"><span class="caption-text">Projects</span></p>
 <ul class="nav bd-sidenav">
@@ -1840,11 +1841,11 @@ plt.show()
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     </a>
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-       href="project1.html"
+       href="week41.html"
        title="next page">
       <div class="prev-next-info">
         <p class="prev-next-subtitle">next</p>
-        <p class="prev-next-title">Project 1 on Machine Learning, deadline October 6 (midnight), 2025</p>
+        <p class="prev-next-title">Week 41 Neural networks and constructing a neural network code</p>
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