121954domain: NAppears in sequencesNumbers k such that k-3, k-5, k-17, k-257, and k-65537 are all primes.at n=27A063825Number of partitions of n into parts but with two kinds of parts of sizes 1 to 10.at n=25A103929Composite numbers k such that k*phi(k) is in A002378.at n=25A256545