125244domain: NAppears in sequencesNumbers k such that the first k binary digits of Pi expressed in decimal forms a prime.at n=12A065987Triangular array read by rows: T(n,k) is the number of functions f:{1,2,...,n}->{1,2,...,n} with exactly k elements x such that |f^(-1)(x)| = 1; n>=0, 0<=k<=n.at n=29A206823