59821

Appears in sequences

• Numbers k such that 7*10^k + 5*R_k + 4 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=10A103062
• Number of (4+2)X(n+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order.at n=13A252965
• Triangle read by rows: T(m,n) is the label of the largest square that an (m,n)-leaper (a generalization of a chess knight) reaches before it can no longer move, starting on a board with squares spirally numbered, starting at 1; 1 <= n < m. Each move is to the lowest-numbered unvisited square.at n=43A306197