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URL: https://oeis.org/A288340

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A288340
a(n) is the smallest prime that is the sum of both 2n-1 and 2n+1 consecutive primes.
3
23, 83, 311, 401, 1367, 3617, 863, 5683, 1523, 153113, 90011, 10949, 7901, 155671, 11131, 117977, 14699, 252079, 58369, 132749, 203293, 641867, 116257, 607093, 78791, 46471, 927049, 340601, 1485541, 521897, 99149, 771889, 2153993, 227869, 2349251, 4762213, 56099, 3232093, 944003, 1006781
OFFSET
1,1
COMMENTS
Inspired by A213174.
Records: 23, 83, 311, 401, 1367, 3617, 5683, 153113, 155671, 252079, 641867, 927049, 1485541, 2153993, 2349251, 4762213, ..., . - Robert G. Wilson v, Jun 11 2017
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 812 terms from Robert G. Wilson v)
MATHEMATICA
pr = Prime@ Range@ 25000; f[n_] := Select[ Intersection[Plus @@@ Partition[pr, 2n -1, 1], Plus @@@ Partition[pr, 2n +1, 1]], PrimeQ][[1]]; Array[f, 40] (* or *)
f[n_] := Block[{a = Prime@ Range[2, 2n], p = Prime[2n +1], b = Prime@ Range[2, 2n +2], q = Prime[2n +3]}, While[aa = Plus @@ a; bb = Plus @@ b; aa != bb || ! PrimeQ@ aa, If[aa < bb, a = Join[Rest@ a, {p}]; p = NextPrime@ p, b = Join[Rest@ b, {q}]; q = NextPrime@ q]]; Plus @@ a]; Array[f, 40]
CROSSREFS
Cf. A213174.
Sequence in context: A167573 A318356 A142790 * A316378 A323147 A262119
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jun 08 2017
STATUS
approved