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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
28, 141, 138, 395, 660, 1425, 1960, 2217, 3810, 5005, 7230 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

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.

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

LINKS

Table of n, a(n) for n=2..12.

CROSSREFS

Cf. A317678, A317679.

Sequence in context: A050973 A095301 A201102 * A042530 A042532 A187608

Adjacent sequences:  A317677 A317678 A317679 * A317681 A317682 A317683

KEYWORD

nonn,more,hard

AUTHOR

Hugo Pfoertner, Aug 10 2018

STATUS

approved

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Last modified June 16 19:49 EDT 2021. Contains 345068 sequences. (Running on oeis4.)