update example

lib/bppsuite.ml

@@ -18,7 +18,7 @@ let conf_file ~tree ~nb_sites =
              input.tree.format=Nhx
              nonhomogeneous = general
              nonhomogeneous.number_of_models = 1
-             model1.nodes_id=0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77
+             model1.nodes_id=0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17
              nonhomogeneous.root_freq=Fixed()
              rate_distribution=Constant()
              output.internal.sequences=no