176399

Appears in sequences

• Numbers that are the product of a pair of twin primes.at n=21A037074
• Product of twin primes of form (4*k+3,4*(k+1)+1), k>=0.at n=11A071700
• Squarefree numbers k such that A076341(k) = 0.at n=29A076352
• Distance from n!+1 to next larger square.at n=13A082995
• Numbers k such that k+1 and sigma(k)+1 are both perfect squares.at n=27A089954
• Numbers that are one less than a square and have exactly 4 divisors.at n=22A134020
• Semiprimes which are sub-perfect powers.at n=32A189045
• Numbers k that form a primitive Pythagorean triple with k' and sqrt(k^2 + k'^2), where k' is the arithmetic derivative of k.at n=24A210503
• Strong Lucas pseudoprimes.at n=20A217255
• G-Lehmer numbers: Composite numbers k such that A060968(k) divides A201629(k).at n=16A235864
• Numbers n which are neither a prime nor a square of a prime such that there is no d, 2<=d<=n/2, which divides binomial(n-d-1,d-1) and is not coprime to n.at n=30A269135
• Composite numbers k such that 2^k == 1 (mod cototient(k)).at n=16A291619
• Numbers k such that k and k+1 are both nonprime-powers whose all distinct prime divisors are consecutive primes (A066312).at n=17A346910
• Numbers k for which k^2 + (k')^2 is a square, where k' is the arithmetic derivative of k (A003415).at n=42A365850
• Numbers k such that k^2 + sopfr(k)^2 is a square, where sopfr = A001414.at n=24A386991