20785

Appears in sequences

• Larger of Smith brothers.at n=12A050220
• Denominators of convergents to Pi by Farey fractions.at n=51A063673
• Indices of primes in sequence defined by A(0) = 21, A(n) = 10*A(n-1) + 61 for n > 0.at n=9A101966
• Minimal peaks in digital expansions of Pi: positions of peaks equal to 1.at n=20A105275
• Numbers k such that (56*10^k + 403)/9 is prime.at n=18A294483