838201

Appears in sequences

• Absolute Euler pseudoprimes: odd composite numbers n such that a^((n-1)/2) == +-1 (mod n) for every a coprime to n.at n=14A033181
• Carmichael numbers with exactly 4 prime factors.at n=16A074379
• a(n) = direuler(p=2,n,1/(1-X)/(1-p*n*X))[n].at n=29A089745
• Carmichael numbers C such that C-1 is not a Niven/Harshad number.at n=7A097061
• a(n) is the smallest Carmichael number (A002997) divisible by the n-th prime, or 0 if no such number exists.at n=34A135721
• Carmichael numbers with more than 3 prime factors.at n=17A141711
• Carmichael numbers of the form C = p*(2p-1)*(n*(2p-2)+p), where p and 2p-1 are prime numbers.at n=14A182207
• Carmichael numbers divisible by 7.at n=15A182208
• The smallest Carmichael number k such that phi(k) does not divide (k-1)^n, where phi is the Euler totient function.at n=2A207080
• Carmichael numbers m such that A309132(m) < m.at n=7A309268
• Carmichael numbers k for which A053575(k) [the odd part of phi] does not divide k-1.at n=29A340092
• Carmichael numbers ending in 1.at n=24A354609
• The lesser of twin Carmichael numbers: a pair of consecutive Carmichael numbers (A002997) without a non-prime-power weak Carmichael number (A087442) between them.at n=5A365022