105741domain: NAppears in sequencesNumbers k such that 11*2^k + 1 is prime.at n=19A002261Number of 5 X n 0..1 arrays with rows nondecreasing and antidiagonals unimodal.at n=12A224136a(n) = Sum_{1 <= x_1, x_2, x_3 <= n} gcd(x_1, x_2, n)/gcd(x_1, x_2, x_3, n).at n=41A373061