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a(0)=1; for n>0, a(n) = smallest prime of the form k*a(n-1)-1 with k>1.
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%I #16 Oct 19 2017 03:14:04

%S 1,2,3,5,19,37,73,1021,8167,16333,326659,3919907,47038883,188155531,

%T 2257866371,76767456613,1535349132259,12282793058071,147393516696851,

%U 4127018467511827,107302480155307501,1502234722174305013

%N a(0)=1; for n>0, a(n) = smallest prime of the form k*a(n-1)-1 with k>1.

%C Conjecture: If a(n) = k*a(n-1)-1 then k < a(n-1).

%C A theorem of Dirichlet shows the sequence to be infinite. - _Don Reble_, Aug 03 2002

%H T. D. Noe, <a href="/A072532/b072532.txt">Table of n, a(n) for n=0..100</a>

%t f[n_]:=Module[{k=2},While[!PrimeQ[k*n-1],k++];k*n-1]; Join[{1}, NestList[ f,2,35]] (* _Harvey P. Dale_, Jun 27 2011 *)

%Y Cf. A061092.

%K nice,nonn

%O 0,2

%A _Amarnath Murthy_, Aug 02 2002

%E More terms from _Don Reble_, Aug 03 2002