I have to admit that I am totally noob to mathematica, and I have a question for which I have not found any easy-to-understand answer about.
How could I calculate the number of prime numbers of a certain form (like, for example, $4n+1$ or $4p+1$ being $p$ prime) lower than a given input $N$? Would there be any way to plot it respect to that $N$?
Thank you!