780889domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes of the form 7n^2 - 3.at n=31A201849Consider the sum of the divisors of a number x>1. Take the sum of its digits. Repeat the process deleting the first addendum and adding the previous sum. The sequence lists the numbers that after some iterations reach x.at n=15A269307Prime numbersat n=62531