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A132830 Numbers of the form 3^n+2 which are not primes. 1
245, 731, 2189, 19685, 177149, 531443, 1594325, 43046723, 129140165, 387420491, 1162261469, 3486784403, 10460353205, 31381059611, 94143178829, 847288609445, 7625597484989, 22876792454963, 68630377364885, 205891132094651 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

a = {}; c = 3^x + 2; Do[If[PrimeQ[c], 0, AppendTo[a, c]], {x, 0, 100}]; a (*Artur Jasinski*)

Select[3^Range[0, 30]+2, !PrimeQ[#]&] (* Harvey P. Dale, Nov 21 2012 *)

CROSSREFS

Cf. A057735, A051783, A132829.

Sequence in context: A137521 A257781 A188239 * A236887 A237161 A056264

Adjacent sequences:  A132827 A132828 A132829 * A132831 A132832 A132833

KEYWORD

nonn

AUTHOR

Artur Jasinski, Sep 03 2007

STATUS

approved

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Last modified September 18 21:53 EDT 2020. Contains 337173 sequences. (Running on oeis4.)