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%I #15 Sep 02 2023 18:52:05
%S 1,3,5,9,11,15,17,23,27,29,33,35,39,41,47,53,57,59,63,65,69,71,75,77,
%T 83,93,95,99,101,105,107,117,127,129,133,135,137,143,147,149,153,155,
%U 159,161,167,173,177,179,185,189,191,195,197,213,221,225,227,233,237,239
%N a(1)=1. a(n) = the smallest odd integer > a(n-1) such that a(n)*2 - a(n-1) is prime.
%H Robert Israel, <a href="/A164121/b164121.txt">Table of n, a(n) for n = 1..10000</a>
%p R:= 1; x:= 1: count:= 1:
%p for y from x+2 by 2 do
%p if isprime(2*y-x) then
%p R:= R, y; x:= y; count:= count+1;
%p if count = 100 then break fi;
%p fi
%p od:
%p R; # _Robert Israel_, Mar 22 2023
%t soi[a_]:=Module[{k=a+2},While[!PrimeQ[2k-a],k=k+2];k]; NestList[soi,1,60] (* _Harvey P. Dale_, Sep 02 2023 *)
%Y Cf. A164122.
%K nonn
%O 1,2
%A _Leroy Quet_, Aug 10 2009
%E More terms from _R. J. Mathar_, Oct 24 2009