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%I #18 Feb 01 2019 02:51:32
%S 3,3,3,3,13,19,43,3,61,13,29,11,5,53,73,53,23,17,229,13,3,3,17,149,5,
%T 239,5,13,223,71,3,11,31,73,97,43,11,83,149,277,311,383,127,11,3,31,
%U 233,61,61,13,73,107,613,137,53,367,467,53,233,277,17,53,109,449,151,97,13,281,103,233,193,23,7
%N Smallest prime q such that 9^n + q*3^n - 1 is prime.
%H Pierre CAMI, <a href="/A214730/b214730.txt">Table of n, a(n) for n = 1..4000</a>
%o (PFGW and SCRIPTIFY)
%o SCRIPT
%o DIM nn,0
%o DIM qq
%o DIMS tt
%o OPENFILEOUT myfile,a(n).txt
%o LABEL loopn
%o SET nn,nn+1
%o IF nn>4000 THEN END
%o SET qq,1
%o LABEL loopq
%o SET qq,qq+1
%o SETS tt,%d,%d\,;nn;p(qq)
%o PRP (3^nn+p(qq))*3^nn-1,tt
%o IF ISPRP THEN GOTO a
%o IF ISPRIME THEN GOTO a
%o GOTO loopk
%o LABEL a
%o WRITE myfile,tt
%o GOTO loopn
%Y Cf. A214700.
%K nonn
%O 1,1
%A _Pierre CAMI_, Jul 27 2012
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