45520

Appears in sequences

• Numbers k such that sigma(k+1) divides sigma(k), where sigma(k) is the sum of positive divisors of k.at n=37A058073
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 5 and 7.at n=46A136899
• Numbers k such that sigma(k) = 2*sigma(k+1).at n=17A163193
• Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically.at n=5A207263
• Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically.at n=5A207267
• Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically.at n=5A207273
• Let b(n) be the number of permutations {c_1..c_n} of {1..n} for which c_1 - c_2 + ... + (-1)^(n-1)*c_n are triangular numbers (A000217). Then a(n) = b(n)/A010551(n).at n=21A294811
• Numbers k such that Bernoulli number B_{k} has denominator 230010.at n=16A295593