24644domain: NAppears in sequencesa(0) = 1, a(n) = 18*n^2 + 2 for n>0.at n=37A010008Number of primes occurring exactly once as numerators in sums generated from the set 1, 1/2, 1/3,..., 1/n.at n=18A217712Number of primes of the form (x+1)^11 - x^11 less than 10^n.at n=51A221983