Calculating Anti-Primes

[Space_Ghost]

I am not seeing anything to improve speed, looks just fine to me. I think a slight advantage with calculations when all the numbers are of the same type and as I recall no advantage using Integers over Long because of 64 bit math. I tried everything Long and got about same time with 3 trials each way.

Thanks bplus !!! This is exactly what I was hoping to understand.  Also appreciate you running the combinatorics on the type options with a 64 bit system and sharing your findings!