399001

Appears in sequences

• Carmichael numbers: composite numbers k such that a^(k-1) == 1 (mod k) for every a coprime to k.at n=28A002997
• Least number for which Solovay-Strassen primality test on bases < prime(n) fails.at n=5A007324
• Least number for which Solovay-Strassen primality test on bases < prime(n) fails.at n=4A007324
• Absolute Euler pseudoprimes: odd composite numbers n such that a^((n-1)/2) == +-1 (mod n) for every a coprime to n.at n=8A033181
• Pseudoprimes to bases 2 and 5.at n=29A083732
• Pseudoprimes to bases 2 and 7.at n=22A083733
• Pseudoprimes to bases 3 and 5.at n=29A083734
• Pseudoprimes to bases 3 and 7.at n=30A083735
• Pseudoprimes to bases 2,5 and 7.at n=11A083736
• Pseudoprimes to bases 2, 3 and 5.at n=22A083737
• Pseudoprimes to bases 2,3 and 7.at n=17A083738
• Pseudoprimes to bases 2, 3, 5 and 7.at n=10A083739
• Pseudoprimes to bases 3,5 and 7.at n=12A083740
• 3-Carmichael numbers: Carmichael numbers equal to the product of 3 primes: k = p*q*r, where p < q < r are primes such that a^(k-1) == 1 (mod k) if a is prime to k.at n=18A087788
• Nonprimes n such that Mod(n,4) == 1 and denominator(Fibonacci((n-1)/4)/n) = 1.at n=17A091982
• Records in A098650.at n=13A098652
• Devaraj numbers: squarefree r-prime-factor (r>1) integers N=p1*...*pr such that phi(N)=(p1-1)*...*(pr-1) divides gcd(p1-1,...,pr-1)^2*(N-1)^(r-2).at n=31A104016
• Nonprime numbers k such that k divides 3^((k+1)/2) - 2^((k+1)/2) - 1.at n=29A130062
• a(n) is the smallest Carmichael number (A002997) with the n-th prime as its smallest prime divisor, or 0 if no such number exists.at n=9A135720
• a(n) is the least Carmichael number of the form prime(n)*prime(n')*prime(n") with n < n' < n", or 0 if no such number exists.at n=10A141705