430199

Appears in sequences

• Composite numbers n such that b^(n+1) == 1 (mod n) for every b coprime to n.at n=34A208728
• Squarefree composite numbers n such that p^2 - 1 divides n^2 - 1 for every prime p dividing n.at n=3A287119
• Composite squarefree numbers k such that k^2-1 is divisible by p-1 and p+1, where p are all the prime factors of k.at n=12A306685