This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A347694 #10 Mar 01 2025 13:51:21
%S A347694 2,4,6,7,10,11,14,14,17,19,22,23,26,26,29,31,34,34,38,38,41,43,46,47,
%T A347694 47,47,53,53,58,59,62,62,62,67,67,71,74,74,74,79,82,83,86,86,89,89,94,
%U A347694 94,97,97,101,103,106,107,109,109,113,113,118,118,122,122,122,127,127,131,134,134,137,139
%N A347694 Largest k <= 2*n such that k is a prime or twice a prime.
%C A347694 Suggested by the formula for A016726.
%H A347694 Harvey P. Dale, <a href="/A347694/b347694.txt">Table of n, a(n) for n = 1..1000</a>
%t A347694 lkp2p[n_]:=Module[{k=2n},While[NoneTrue[{k,k/2},PrimeQ],k--];k]; Array[lkp2p,200] (* _Harvey P. Dale_, Mar 01 2025 *)
%Y A347694 Cf. A016726, A347693.
%K A347694 nonn
%O A347694 1,1
%A A347694 _N. J. A. Sloane_, Oct 05 2021