This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A317680 #14 Sep 01 2018 02:02:00
%S A317680 28,141,138,395,660,1425,1960,2217,3810,5005,7230
%N A317680 Least sum S_n of n distinct primes p_i such that q_j = n*p_j - Sum_{k=1..n,k!=j} p_k, j=1..n is prime, such that the set union {p_i} U {q_i} contains 2*n distinct primes.
%C A317680 The sets of primes p_i and q_i and a description of the problem are provided in A317678 and A317679. a(1) is omitted to indicate the nonexistence of a solution.
%C A317680 a(13) <= 8955, a(14) <= 12122.
%Y A317680 Cf. A317678, A317679.
%K A317680 nonn,more,hard
%O A317680 2,1
%A A317680 _Hugo Pfoertner_, Aug 10 2018