517496

Appears in sequences

• Triangle T(n,k) = P(n,k)/2, n >= 2, 1 <= k < n, of one-half of number of permutations of 1..n such that the differences have k runs with the same signs.at n=42A008970
• Third diagonal of A008970 (after A000111 and A000708).at n=6A091303