%I #15 Jun 20 2023 16:09:05
%S 1,2,3,5,6,7,10,12,15,17,24,30,42,54,57,60,63,72,74,83,84,91,96,104,
%T 106,120,123,129,138,139,144,147,149,153,155,203,219,240,245,259
%N Records in A016014.
%t km = 0; Reap[Do[k = 1; While[ ! PrimeQ[2*n*k + 1], k++]; If[k > km, km = k; Sow[k]], {n, 20000}]][[2, 1]]
%t lk[n_]:=Module[{k=1},While[!PrimeQ[2n k+1],k++];k];DeleteDuplicates[Array[ lk,10^7],GreaterEqual] (* _Harvey P. Dale_, Jun 20 2023 *)
%o (PARI) A016014(n)=my(k); while(!isprime(2*n*k+++1), ); k
%o r=0; for(n=1, 1e8, t=A016014(n); if(t>r, r=t; print1(r", "))) \\ _Jianing Song_, Mar 09 2021, based on the program of A239727
%Y Cf. A016014, A239727.
%K nonn,more
%O 1,2
%A _Zak Seidov_, Mar 26 2014
%E a(37)-a(40) from _Giovanni Resta_, Mar 26 2014
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