157651domain: NAppears in sequencesStrong pseudoprimes to base 29.at n=28A020255Number of ordered quintuples (a,b,c,d,e) with gcd(a,b,c,d,e)=1 (1<= {a,b,c,d,e} <= n).at n=10A082544Numbers k such that k^p-p is prime, where p is product of the digits of k.at n=42A178328