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 A186946 #21 Apr 08 2024 06:54:37
%S A186946 2,3,5,9,13,25,29,31,43,49,71,73,81,103,109,113,127,131,139,157,173,
%T A186946 181,191,193,199,239,241,269,271,283,289,293,313,349,353,361,373,379,
%U A186946 409,419,421,433,439,443,463,499,509,523,571,577,599,601,607,613,619
%N A186946 The smallest integer x > 0 such that the number of prime powers p^k (k>=1) in (x/2,x] equals n.
%C A186946 An analog of Labos primes (A080359) on prime powers > 1 (A000961).
%H A186946 Peter J. C. Moses, <a href="/A186946/b186946.txt">Table of n, a(n) for n = 1..10000</a>
%F A186946 a(n) <= A186945(n).
%t A186946 a000961Q[n_]:=(Length[FactorInteger[n]]==1) && IntegerQ[n]; nn=99; t=Table[0,{nn+1}]; s=0; Do[If[a000961Q[k], s++]; If[a000961Q[k/2], s--]; If[s<=nn && t[[s+1]]==0, t[[s+1]]=k], {k, 2, Prime[3*nn]}]; Prepend[Rest[t],2] (* after T. D. Noe's code at A080359 *) (* _Peter J. C. Moses_, Sep 11 2013 *)
%Y A186946 Cf. A080459, A186945, A228520, A228592.
%K A186946 nonn
%O A186946 1,1
%A A186946 _Vladimir Shevelev_, Aug 30 2013
%E A186946 More terms from _Peter J. C. Moses_, Aug 30 2013