Is there software available anywhere that implements an efficient algorithm for counting primes in residue classes? Something along the lines of, say,

Deléglise-Dusart-Roblot 2004. (They did implement their own algorithm, using it to compute, e.g.,

A091099(20), but as far as I know that's not available -- and in any case it would be 17 years old, and targeting the

Alpha and the

P3. Still, if it's out there I'd like to know.)