24513

Appears in sequences

• Numbers n such that 2^n - 21 is prime.at n=27A057202
• Numbers k such that 2^k - 21 is prime.at n=23A096820
• Not appropriate for the OEIS.at n=10A248690
• Decimal encoding T(n,k) of the k-th non-averaging permutation of [n]; triangle T(n,k), n >= 0, k = 1..A003407(n), read by rows.at n=24A292523
• Derangements of {1,2,...,n} (n >= 2) in lexicographic order.at n=18A320588
• a(1) = 1; a(n+1) = Sum_{k=1..n} a(k) * ceiling(n/k).at n=12A332846