33177domain: NAppears in sequencesBecomes prime or 4 after exactly 9 iterations of f(x) = sum of prime factors of x.at n=30A048131Row sums of triangle A179901.at n=26A179902L.g.f.: log(Product_{k>=1} (1 + x^k/(1 + x))) = Sum_{k>=1} a(k)*x^k/k.at n=14A307762