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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. 2

%I

%S 28,141,138,395,660,1425,1960,2217,3810,5005,7230

%N 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 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 a(13) <= 8955, a(14) <= 12122.

%Y Cf. A317678, A317679.

%K nonn,more,hard

%O 2,1

%A _Hugo Pfoertner_, Aug 10 2018

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Last modified July 24 10:49 EDT 2021. Contains 346273 sequences. (Running on oeis4.)