120581

Appears in sequences

• Lucas-Carmichael numbers: squarefree composite numbers k such that p | k => p+1 | k+1.at n=28A006972
• Numbers n such that n divides the (left) concatenation of all numbers <= n written in base 18 (most significant digit on right).at n=7A061971
• Odd composite n such that n divides Fibonacci(n) + 1.at n=7A094395
• Odd composites k that divide Fibonacci(k) + 1 but not Fibonacci(k+1).at n=1A094413
• Lucas-Carmichael numbers that are not congruent to 11 (mod 12).at n=4A110885
• Composite terms in A128288(n) = A023163(n)/3 for n>1.at n=9A128289
• Lucas-Carmichael numbers with 3 prime factors.at n=20A216925
• Lucas-Carmichael numbers that are congruent to 1 (mod 4).at n=2A292021