52739

Appears in sequences

• Base-9 palindromes that start with 8.at n=23A043035
• Numbers k such that 40*R_k + 9 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=8A056683
• Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 10000-11111-00001 pattern in any orientation.at n=20A147071