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 A081306 #14 Mar 04 2019 22:57:10
%S A081306 1,2,3,4,5,6,7,8,9,11,12,13,15,16,17,18,19,23,24,25,27,29,31,32,35,36,
%T A081306 37,41,43,45,47,48,49,53,54,59,61,64,67,71,72,73,75,77,79,81,83,89,91,
%U A081306 96,97,101,103,107,108,109,113,121,125,127,128,131,135,137,139,143,144
%N A081306 Numbers n with prime factors less than 2*spf(n), where spf(m) is the smallest prime factor of m (A020639).
%C A081306 A081303(a(n)) < 0, A006530(a(n)) < A020639(a(n))*2.
%H A081306 Robert Israel, <a href="/A081306/b081306.txt">Table of n, a(n) for n = 1..10000</a>
%p A081306 filter:= proc(n) local F;
%p A081306 F:= numtheory:-factorset(n);
%p A081306 max(F) < 2*min(F);
%p A081306 end proc:
%p A081306 select(filter, [$1..200]); # _Robert Israel_, Mar 28 2018
%t A081306 Select[Range[200], Max[F = FactorInteger[#][[All, 1]]] < 2 Min[F]&] (* _Jean-François Alcover_, Mar 04 2019 *)
%Y A081306 Cf. A006530, A020639, A081303.
%Y A081306 Complement of A069900.
%Y A081306 Union of {1} and A069899. [_R. J. Mathar_, Sep 18 2008]
%K A081306 nonn
%O A081306 1,2
%A A081306 _Reinhard Zumkeller_, Mar 17 2003