26611307domain: NAppears in sequencesNumerator of Sum_{i = 1..n} (if(isprime(i), 0, 1/i)).at n=29A282501Numerator of Sum_{i = 1..n} (if(isprime(i), 0, 1/i)).at n=30A282501Numerator of the sum of the reciprocals of the first n nonprimes.at n=19A282511