6474691domain: NAppears in sequencesSarrus numbers k such that k-1 and k+1 have the same number of prime divisors (counted with multiplicity).at n=24A086806Increasing gaps between 2-pseudoprimes (upper end).at n=23A175737Fermat pseudoprimes (A001567) that are the sum of three consecutive primes.at n=28A270639