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a(1) = 2; a(n) is smallest prime > 3*a(n-1).
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%I #15 Oct 19 2017 03:14:07

%S 2,7,23,71,223,673,2027,6089,18269,54829,164503,493523,1480571,

%T 4441721,13325171,39975553,119926691,359780077,1079340313,3238020943,

%U 9714062893,29142188683,87426566057,262279698173,786839094529

%N a(1) = 2; a(n) is smallest prime > 3*a(n-1).

%H Harvey P. Dale, <a href="/A076656/b076656.txt">Table of n, a(n) for n = 1..1000</a>

%t PrimeNext[n_]:=Module[{k},k=n+1;While[ !PrimeQ[k],k++ ];k]; p=2;lst={p};Do[p=PrimeNext[3*p];AppendTo[lst,p],{n,2*4!}];lst (* _Vladimir Joseph Stephan Orlovsky_, May 27 2009 *)

%t NestList[NextPrime[3#]&,2,30] (* _Harvey P. Dale_, Aug 12 2016 *)

%Y Cf. A055496.

%K nonn

%O 1,1

%A _Cino Hilliard_, Oct 24 2002

%E Edited by _Don Reble_, May 03 2006