275456domain: NAppears in sequencesConjectured largest number having n representations as the sum of two twin primes p + q with p >= q.at n=22A212613Integers x such that there exist four integers 0<y<=z<=t<=w such that psi(x)^4 = x^4 + y^4 + z^4 + t^4 + w^4.at n=4A391536