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 A320681 #4 Oct 19 2018 10:27:29 %S A320681 0,1,7,20,51,117,239,430,724,1163,1834,2823,4252,6226,8870,12299, %T A320681 16712,22340,29524,38606,49979,63965,80946,101250,125316,153592, %U A320681 186694,225268,270172,322285,382716,452614,533380,626424,733387,855881,995740,1154735,1334850 %N A320681 Number of 6-element subsets of [n] having a prime element sum. %H A320681 Alois P. Heinz, <a href="/A320681/b320681.txt">Table of n, a(n) for n = 6..500</a> %Y A320681 Column k=6 of A282516. %K A320681 nonn %O A320681 6,3 %A A320681 _Alois P. Heinz_, Oct 19 2018