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 A290334 #14 Apr 09 2021 22:17:44
%S A290334 1,2,4,5,7,8,11,12,14,17,19,22,24,26,27,29,31,32,34,37,38,41,43,44,47,
%T A290334 50,52,53,59,62,68,71,77,80,85,86,89,92,94,95,97,98,101,103,104,106,
%U A290334 107,110,112,113,115,116,119,121,122,124,125,128,130,131,133,134,137,138,140,143,145,147,148,150,152,155,157,158,160,164,165
%N A290334 Numbers that are not the sum of three or fewer terms from A020330.
%C A290334 Not currently proved that there are infinitely many terms. It is conjectured that all integers > 686 are the sum of four binary squares.
%H A290334 Amiram Eldar, <a href="/A290334/b290334.txt">Table of n, a(n) for n = 1..10000</a>
%H A290334 Aayush Rajasekaran, Jeffrey Shallit and Tim Smith, <a href="https://drops.dagstuhl.de/opus/volltexte/2018/8497">Sums of Palindromes: an Approach via Nested-Word Automata</a>, in: Rolf Niedermeier and Brigitte Vallée, 35th Symposium on Theoretical Aspects of Computer Science (STACS 2018), Schloss Dagstuhl, 2018, pp. 54:1-54:12; <a href="https://arxiv.org/abs/1706.10206">arXiv preprint</a>, arXiv:1706.10206 [cs.FL], June 30 2017.
%t A290334 v = Table[n + n * 2^Floor[Log2[n] + 1], {n, 0, 12}]; Complement[Range[v[[-1]]], Plus @@@ Tuples[v, 3]] (* _Amiram Eldar_, Apr 09 2021 *)
%Y A290334 Cf. A020330, A290335, A298731.
%K A290334 nonn
%O A290334 1,2
%A A290334 _Jeffrey Shallit_, Jul 27 2017