181421

Properties

Appears in sequences

• Let f(m) = smallest composite number that takes m steps of "add prime factors to number" to reach a prime and g(m) be the prime that is reached. Sequence gives values of g(m), sorted and duplicates removed.at n=14A050767
• Beginning with 3, least member of A007500 such that concatenation of first n terms and its digit reversal both are primes.at n=27A111383
• Closest pair of primes p <= q such that p + q = n! Sequence gives the lesser member p of the pair.at n=6A137982
• Numbers k such that 2^(k-1) == 1 + b*k (mod k^2), where b divides k - 2^p for some integer p >= 0 and 2^p <= b.at n=54A186884
• Prime numbersat n=16446