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 A289898 #30 Aug 03 2017 04:39:14
%S A289898 2,2,2,11,3,12,3,12,59,3,51,15,3,12,59,62,3,51,15,3,50,15,60,251,15,3,
%T A289898 12,3,12,15179,15,60,3,816,3,51,62,15,60,62,3,816,3,12,3,3226,4094,15,
%U A289898 3,12,59,3,816,63,63,63,3,51,15,3,808,16363,15,3,12,15183
%N A289898 a(n) = floor((2^prime(n+1))/Sum_{k=0|n,2^prime(k)}).
%F A289898 a(n) = floor(2^prime(n+1)/(Sum_{k=1..n} 2^prime(k))).
%t A289898 Table[Floor[2^Prime[n + 1]/Sum[ 2^Prime[k], {k, n}]], {n, 66}] (* _Michael De Vlieger_, Jul 16 2017 *)
%o A289898 (PARI) a(n) = 2^prime(n+1)\sum(k=1, n, 2^prime(k)); \\ _Michel Marcus_, Jul 16 2017
%Y A289898 Cf. A034785, A076793.
%K A289898 nonn
%O A289898 1,1
%A A289898 _Joseph Wheat_, Jul 14 2017