19384289

Appears in sequences

• Carmichael numbers that are not == 1 mod 12. There are 69 Carmichael numbers out to 2*m+1, m=2*10^6 and all but the above 9 are 1 mod 12.at n=14A110889
• 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=22A135720
• 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=23A141705
• Carmichael numbers that only have composite XOR couples as defined in A182108.at n=1A182116
• Carmichael numbers not congruent to 1 modulo 6.at n=8A205947
• Carmichael numbers k such that the odd part of k-1 is squarefree.at n=19A263403
• Carmichael numbers n such that n-1 is not a practical number.at n=7A265827
• The least 3-Carmichael number that is divisible by the n-th odd prime, or 0 if no such number exists.at n=22A290486
• Carmichael numbers whose prime factors form an arithmetic progression.at n=7A300949
• Primary Carmichael numbers.at n=29A324316
• Imprimitive Carmichael numbers: Carmichael numbers m such that if m = p_1 * p_2 * ... *p_k is the prime factorization of m then g(m) = gcd(p_1 - 1, ..., p_k - 1) > sqrt(lambda(m)), where lambda is the Carmichael lambda function (A002322).at n=14A328935
• Carmichael numbers (A002997) that are not minimal in their family.at n=7A335584
• Carmichael numbers ending in 9.at n=9A352970
• Composites that cause a witness to be added to a set of Fermat witnesses: a(n) is the smallest composite number that is not guaranteed composite using Fermat's Little Theorem by the witness A380978(i) for any i < n.at n=23A380979