Update week3.do.txt

Author: mhjensen

doc/src/week3/week3.do.txt

@@ -6,9 +6,9 @@ DATE: February 4, 2026
 !split
 ===== Plans for the week of February 3-7, 2025 =====
 !bblock
+o Density matrices, Entanglement, Bell states and entropy
 o Quantum circuits and operations (one-, two- and three-qubit gates
 o Hands-on exercises, see end of these slides
-o Discussion of the first exercise of project 1
 #o "Video of lecture":"https://youtu.be/9XrDKgTQL6I"
 #o "Whiteboard notes":"https://github.com/CompPhysics/QuantumComputingMachineLearning/blob/gh-pages/doc/HandWrittenNotes/2024/NotesFebruary14.pdf"
 !eblock