We hebben je patroon gecontroleerd op zin 1 tot en met 442 van de nl Wikipedia, Tatoeba en verschillende online fora
Just 442 test sentences? I guess it is intended as the selected 442 sentences.
That’s just the number of sentences that were actually analyzed. The system skipped a few hundred thousand sentences that didn’t match (because it found they cannot match anyway).
That is not what the text says imho.