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 A331237 #9 Jan 17 2020 17:45:56
%S A331237 0,0,1,5,15,47,127,363,978,2778,7624,21566,60584,172221,488978,
%T A331237 1398457,4001323,11490717,33037548,95195793,274609124,793298293,
%U A331237 2294114542,6641070332,19241453969,55795142707,161910611244
%N A331237 Total cutting number of all trees of order n.
%H A331237 Frank Harary and Peter J. Slater, <a href="https://doi.org/10.1016/0020-0190(86)90093-1">A linear algorithm for the cutting center of a tree</a>, Information Processing Letters, 23 (1986), 317-319.
%H A331237 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a331/A331237.java">Java program</a> (github)
%F A331237 a(n) = Sum_{T} c(T) where the sum is over all trees with n vertices and c(T) is the cutting number of T.
%F A331237 a(n) = Sum_{k=0..(n-1)*(n-2)/2} A331238(n, k).
%Y A331237 Cf. A002887, A002888, A331236, A331238.
%K A331237 nonn,more
%O A331237 1,4
%A A331237 _Sean A. Irvine_, Jan 13 2020