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A034784 Numbers n such that A034693(n) = 2. 6
3, 5, 8, 9, 11, 14, 15, 20, 21, 23, 26, 29, 33, 35, 39, 41, 44, 48, 50, 51, 53, 54, 56, 63, 65, 68, 69, 74, 75, 81, 83, 86, 89, 90, 95, 98, 99, 105, 111, 113, 114, 116, 119, 120, 125, 128, 131, 134, 135, 140, 141, 146, 153, 155, 158, 165, 168, 173, 174, 176 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

MATHEMATICA

CompositeNext[n_]:=Module[{k=n+1}, While[PrimeQ[k], k++ ]; k]; lst={}; Do[p=n+CompositeNext[n]; If[PrimeQ[p], AppendTo[lst, n]], {n, 2, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jun 15 2009 *)

Position[#, 2] &@ Table[k = 1; While[! PrimeQ[k n + 1], k++]; k, {n, 180}] // Flatten (* Michael De Vlieger, Mar 02 2017 *)

CROSSREFS

Cf. A034693, A034694.

Sequence in context: A108594 A286048 A026223 * A190280 A261786 A124401

Adjacent sequences:  A034781 A034782 A034783 * A034785 A034786 A034787

KEYWORD

nonn

AUTHOR

Labos Elemer

EXTENSIONS

Edited by N. J. A. Sloane, Oct 27 2012

STATUS

approved

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Last modified December 19 10:10 EST 2018. Contains 318246 sequences. (Running on oeis4.)