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 A227358 #51 Dec 02 2024 16:29:58 %S A227358 0,1,4,11,23,45,82,129,208,309 %N A227358 Length of shortest Golomb-like (for sums of triples) ruler with n marks. %C A227358 a(n) is the least integer such that there is an n-element set of integers between 0 and a(n), the sums of triples (of not necessarily distinct elements) of which are distinct. %C A227358 a(11) = 445 or a(11) < 440, but disproving the latter will take many cpu-years with the given program. - _John Tromp_, Aug 28 2013 %H A227358 IBM Research, <a href="https://research.ibm.com/haifa/ponderthis/challenges/July2013.html">Ponder This, July 2013</a> essentially asks for a(8). %H A227358 Kevin O'Bryant, <a href="https://arxiv.org/abs/2308.12406">Constructing Thick B_h sets</a>, arXiv:2308.12406 [math.NT], 2023. %H A227358 John Tromp, <a href="/A227358/a227358.c.txt">PonderThisJuly2013.c</a> %F A227358 a(n) = A227588(n,3) - 1. - _James Wilcox_, Aug 02 2013 %e A227358 a(4) = 11 because 0-1-7-11 (0-4-10-11) and 0-1-8-11 (0-3-10-11) have all (6 choose 3)=20 distinct triple sums and there is no 0=b0<b1<b2<b3<11 with distinct triple sums. %o A227358 (C) // See link. %Y A227358 Cf. A003022, A227588. %K A227358 nonn,hard,more %O A227358 1,3 %A A227358 _John Tromp_, Jul 08 2013 %E A227358 a(8)-a(10) from _John Tromp_, Jul 30 2013