private static BitArray MakeSieve(PrimeNumbers primes, int until)
{
until++;
var bits = new BitArray(until);
bits[0] = true;
bits[1] = true;
foreach (var prime in primes.Until((int)Math.Sqrt(until)))
{
for (int i = prime * 2; i < until; i += prime)
{
bits[i] = true;
}
}
return(bits.Not());
}
public PrimeNumbers(PrimeNumbers primes, int until) : this(MakeSieve(primes, until))
{
}