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 A085783 #10 May 15 2018 09:01:38
%S A085783 2,3,5,6,7,9,11,12,13,15,17,18,19,20,21,23,29,30,31,33,37,39,41,42,43,
%T A085783 45,47,50,51,53,56,57,59,61,63,66,67,69,70,71,72,73,75,78,79,83,84,87,
%U A085783 89,90,93,97,101,102,103,105,107,108,109,110,111
%N A085783 Product of a prime and a triangular number.
%H A085783 Robert Israel, <a href="/A085783/b085783.txt">Table of n, a(n) for n = 1..10000</a>
%e A085783 15 = 5*t(2) is a term.
%p A085783 N:= 200: # for all terms <= N
%p A085783 T:= [seq(i*(i+1)/2,i=1..floor((sqrt(4*N+1)-1)/2))]:
%p A085783 P:= select(isprime,[2,seq(i,i=3..N,2)]):
%p A085783 sort(select(`<=`,convert({seq(seq(p*t,p=P),t=T)},list),N)); # _Robert Israel_, May 15 2018
%Y A085783 Cf. A000040, A000217.
%Y A085783 A196421 is a subsequence. - _Michel Marcus_, May 15 2018
%K A085783 nonn
%O A085783 1,1
%A A085783 _Jon Perry_, Jul 23 2003
%E A085783 107 and 109 inserted by _Robert Israel_, May 15 2018