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 A007187 M2532 #33 May 03 2019 21:35:27 %S A007187 1,3,6,9,15,20,26,34,41 %N A007187 Leech's tree-labeling problem for n nodes. %C A007187 a(11) >= 48, a(12) >= 55. %C A007187 a(n) is the greatest number k such that there exists a tree with n nodes and integral edge labels such that for each integer 1 <= m <= k, there exists a pair of nodes such that the sum of the edge labels on the path connecting the two nodes equals m. - _Charlie Neder_, Apr 26 2019 %D A007187 R. K. Guy, Unsolved Problems in Number Theory, Sect. C10. %D A007187 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A007187 R. K. Guy, <a href="https://www.jstor.org/stable/2324219">A quarter century of "Monthly" unsolved problems</a>, 1969-1993, Amer Math. Monthly, 100 (1993), 945-949. %H A007187 J. Leech, <a href="https://doi.org/10.1112/jlms/s1-31.2.160">On the representation of 1, 2, ..., n by differences</a>, J. Lond. Math. Soc. 31 (1956), 160-169. %H A007187 <a href="/index/Tra#trees">Index entries for sequences related to trees</a> %Y A007187 Cf. A005488. %K A007187 nonn,hard,nice,more %O A007187 2,2 %A A007187 _N. J. A. Sloane_