276013

Appears in sequences

• Composite numbers k such that 2^k-2 and 3^k-3 are both divisible by k and k is not a Carmichael number (A002997).at n=15A153513
• Numbers m such that exactly half of the a such that 0<a<m and (a,m)=1 satisfy a^(m-1) == 1 (mod m).at n=36A191311
• Numbers in A191311 but not in A129521.at n=18A191592
• Pseudoprimes divisible by a smaller pseudoprime.at n=19A215150
• Fermat pseudoprimes to base 2 with three prime factors divisible by a smaller Fermat pseudoprime to base 2.at n=4A215944
• Composite integers k such that 2^k == 2 (mod k*(k+1)).at n=31A217465
• Odd numbers k > 1 such that 2^((k-1)/2) == -(2/k) = -A091337(k) (mod k), where (2/k) is the Jacobi (or Kronecker) symbol.at n=13A306310