erfc(x) takes seconds from x = 70, and past 20 s from x = 100 #1606

What you ran: MathS.Erfc(100).EvalNumerical() (AngouriMath, master at f300ee7).

What it did: It did not return within 20 s, and neither did erfc(300) or erfc(1000). The time grows with the argument: erfc(20) 148 ms, erfc(50) 655 ms, erfc(70) 5.3 s.

What it should have done: Return 0 at once, as erfc(20) does. erfc(100) is about 6.4e-4346, below what the default precision context represents. That is how Number.Erfc's documentation describes erfc(30).