387731

Appears in sequences

• Sarrus numbers k such that k-1 and k+1 have the same number of prime divisors (counted with multiplicity).at n=7A086806
• Pseudoquadprimes: p+4 for primes p where p+4 divides p^(p+4) + 4 and p+4 is composite.at n=28A100875
• Increasing gaps between 2-pseudoprimes (upper end).at n=16A175737
• Pseudoprimes to base 2 of the form 4k+3.at n=18A177884
• Pseudoprimes divisible by a smaller pseudoprime.at n=24A215150
• Fermat pseudoprimes to base 2 with three prime factors divisible by a smaller Fermat pseudoprime to base 2.at n=8A215944
• Numbers k such that 2^(k-1) == 1 (mod k) and lpf(k)-1 does not divide k-1.at n=18A316906