24075domain: NAppears in sequencesa(n) is the sum of all possible pairs of the first n primes.at n=23A162867Numbers k such that 3k-4, 3k-2, 3k+2, and 3k+4 are primes.at n=30A173092Eigentriangle for the Catalan triangle (c(x), xc(x)), A033184.at n=58A181644Numbers k such that 3*4^k+1 is prime.at n=18A326655