If it's no more than 5% of the features, it's actually n-choose-k(100,5) + n-choose-k(100,4) + n-choose-k(100,3) + n-choose-k(100,2) + 100! 75,287,520 +

If it's no more than 5% of the features, it's actually n-choose-k(100,5) + n-choose-k(100,4) + n-choose-k(100,3) + n-choose-k(100,2) + 100! 75,287,520 + 3,921,225 + 161,700 + 4,950 + 100 ------------ 79,375,495