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A214680 a(1)=3; a(n) is the smallest prime of the form k*a(n-1) + 2. 1

%I #20 Feb 20 2019 14:59:31

%S 3,5,7,23,71,73,367,1103,7723,131293,3807499,19037497,57112493,

%T 1427812327,15705935599,141353420393,989473942753,44526327423887,

%U 311684291967211,4675264379508167,4675264379508169,275840598390981973,4137608975864729597

%N a(1)=3; a(n) is the smallest prime of the form k*a(n-1) + 2.

%C Up to the end of the b-file, there are only 4 pairs of twin primes in the sequence, with lesser twin primes 3, 5, 71 and 4675264379508167. - Editors, Feb 20 2018

%H Michael De Vlieger, <a href="/A214680/b214680.txt">Table of n, a(n) for n = 1..399</a>

%t t = {3}; Do[k = 1; While[p = k*t[[-1]] + 2; ! PrimeQ[p], k++]; AppendTo[t, p], {25}]; t (* _T. D. Noe_, Jul 26 2012 *)

%Y Cf. A061092, A059411, A214523.

%K nonn

%O 1,1

%A _Robin Garcia_, Jul 25 2012

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)