56975

Appears in sequences

• Number of discordant permutations.at n=22A000561
• Numbers k such that sigma(k) divides sigma(k+1), where sigma(k) is sum of positive divisors of k.at n=36A058072
• Numbers k such that k and k+1 have the same sum of squarefree divisors, or sqf(k) = sqf(k+1), where sqf(k) = A048250(k).at n=19A063964
• Numbers k such that sigma(k+1) = 2*sigma(k).at n=12A067081
• a(n) = smallest number k such that 2^n + k is a palindrome.at n=35A083463