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             Logistic Models -- Stretch Your Understanding

The cell  below gives one example of a more realistic model based on the same ideas as logistic models.  Evaluate it now and then use it as the basis for further experiments.
;[s]
3:0,2;58,0;165,1;235,-1;
3:1,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,65535,0,0;1,13,9,Times,1,12,0,0,0;
:[font = input; preserveAspect; ]
Clear[R, f, pop, a]

a := 2.00

R[p_] := If[p < 500, a, a - a(p - 500)/1500]

f[p_] := R[p] p

pop[1] := 50
pop[n_] := f[pop[n - 1]]

ListPlot[Table[{i, pop[i]}, {i, 1, 20}],
         PlotJoined -> True,
         PlotRange -> {0, 2000}]
^*)