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 A273812 #23 Apr 23 2018 04:05:12 %S A273812 1,535903,1072327,1594807,1750111,2025783,2822151,3304447,3566119, %T A273812 3697543,3855319,3982759,4874439,5832831,5930775,6642975,7115791, %U A273812 7536567,7591447,7885135,8058399,8225991,8307879,8357079,8900583,9339775,10071879,10626655,11274735,11334943,12046807,12229255 %N A273812 Numbers that cannot be expressed as the sum of two nonzero squares and at most two powers of two. %C A273812 If up to three powers of 2 are allowed (instead of two), then the smallest n > 1 which cannot be expressed is larger than 10^10. - _Giovanni Resta_, Jun 08 2016 %C A273812 Smallest n > 1 that can't be written as the sum of two squares and at most three powers of two is larger than 2^36. - _David J. Platt_, Aug 11 2016 %H A273812 R. C. Crocker, <a href="https://www.impan.pl/en/publishing-house/journals-and-series/colloquium-mathematicum/all/112/2/87281/on-the-sum-of-two-squares-and-two-powers-of-k">On the sum of two squares and two powers of k</a>, Colloq. Math. 112(2008), 235-267. %H A273812 Dave Platt, Tim Trudgian, <a href="https://arxiv.org/abs/1610.01672">On the sum of two squares and at most two powers of 2</a>, arXiv:1610.01672 [math.NT], 2016. %Y A273812 Cf. A000404, A274050. %K A273812 nonn %O A273812 1,2 %A A273812 _David J. Platt_, May 31 2016