50145

Appears in sequences

• Coefficient of x in the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.at n=19A192982
• Triangle read by rows: T(n,k) (n>=1, 1 <= k <= n) = number of n-element unlabeled rigid interval posets of height k.at n=58A193357
• a(n) = smallest number k such that (k + n)' = k', or -1 if no such number exists, where k' is the arithmetic derivative of k.at n=12A255354