@Preben Alsholm 

Thanks very much. Your code was quite effective and was able to give graphs which I was earlier not able to get and also the recursive procedure is a good way to store all solutions.

Is there a way using recursion by which I can plot all the plots I need in same graph for the purpose of making comparison.
And also getting solutions of P in terms of a rather than numerical solutions at each a. 

@acer

Thanks very much. I was able to get rid of rtable thing popping up.
and yes I declared D as top level local earlier but now I did it with DD as you suggested .

Sukhdarshan