ENH: migrate ak2 from intro lecture series

lectures/_static/quant-econ.bib

@@ -2521,4 +2521,23 @@ @book{Brunton_Kutz_2019
   publisher = {Cambridge University Press}, 
   author    = {Brunton, Steven L. and Kutz, J. Nathan}, 
   year      = {2019}
+}
+
+@article{diamond1965national,
+  title     = {National debt in a neoclassical growth model},
+  author    = {Diamond, Peter A},
+  journal   = {The American Economic Review},
+  volume    = {55},
+  number    = {5},
+  pages     = {1126--1150},
+  year      = {1965},
+  publisher = {JSTOR}
+}
+
+@book{auerbach1987dynamic,
+  title   = {Dynamic fiscal policy},
+  author  = {Auerbach, Alan J and Kotlikoff, Laurence J},
+  publisher = {Cambridge University Press},
+  address = {Cambridge},
+  year    = {1987}
 }

lectures/_toc.yml

@@ -11,7 +11,6 @@ parts:
   - file: svd_intro
   - file: var_dmd
   - file: newton_method
-
 - caption: Elementary Statistics
   numbered: true 
   chapters:
@@ -24,13 +23,11 @@ parts:
   - file: back_prop
   - file: rand_resp
   - file: util_rand_resp
-
 - caption: Linear Programming
   numbered: true
   chapters:
   - file: opt_transport
   - file: von_neumann_model
-
 - caption: Introduction to Dynamics
   numbered: true
   chapters:
@@ -57,6 +54,7 @@ parts:
   chapters:
   - file: cass_koopmans_1
   - file: cass_koopmans_2
+  - file: ak2
   - file: cake_eating_problem
   - file: cake_eating_numerical
   - file: optgrowth
@@ -84,7 +82,6 @@ parts:
   - file: likelihood_bayes
   - file: mix_model
   - file: navy_captain
-
 - caption: LQ Control
   numbered: true
   chapters: