64377991

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=17A110889
• Carmichael numbers of the form C = (30n-17)*(90n-53)*(150n-89).at n=3A182133
• Carmichael numbers congruent to 3 modulo 4.at n=6A185321
• Carmichael numbers that are not of the form x^2 + y^2 + z^2 where x, y and z are integers.at n=4A267462
• Carmichael numbers whose prime factors form an arithmetic progression.at n=9A300949
• 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=19A328935
• Carmichael numbers all of whose prime factors are congruent to 3 modulo 4.at n=13A329468
• Odd squarefree composite numbers k such that p-1 divides k-1 and p-1 does not divide (k-1)/2 for every prime p|k.at n=11A329799
• Carmichael numbers (A002997) that are not minimal in their family.at n=10A335584
• 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=28A380979
• Carmichael numbers with exactly 3 prime factors, p*q*r, such that p-1, q-1 and r-1 have an equal 2-adic valuation.at n=11A382791