546391domain: NPropertiesPrimalityPrimeyesAppears in sequencesa(1) = 1; a(n+1) = (Product_{k = 1..n} [a(k)]) * (Sum_{j = 1..n} [1/a(j)]).at n=6A057438Primes p followed by a gap of 70 = nextprime(p) - p.at n=13A204792Lower ends of record gaps between numbers that are either prime or twice a prime.at n=18A290488Prime numbersat n=45053