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 A080288 #74 Jun 27 2025 23:27:45 %S A080288 1,2,3,8,9,10,12,20,27,30,34,39,41,42,69,78,100,122,137,262,315,587, %T A080288 609,631,758,890,1083,1092,1114,1364,1373 %N A080288 Successively larger gaps between Ulam numbers. %C A080288 The lower term of the gaps is in A080287. %H A080288 Philip Gibbs and Judson McCranie, <a href="https://www.researchgate.net/profile/Philip_Gibbs/publication/320980165_The_Ulam_Numbers_up_to_One_Trillion/links/5a058786aca2726b4c78588d/The-Ulam-Numbers-up-to-One-Trillion.pdf">The Ulam Numbers up to One Trillion</a>, (2017). %H A080288 Shyam Sunder Gupta, <a href="https://doi.org/10.1007/978-981-97-2465-9_18">Ulam Numbers</a>. In: Exploring the Beauty of Fascinating Numbers. Springer Praxis Books(). Springer, Singapore, (2025). %e A080288 87 and 97 are successive Ulam numbers and this is the first gap of 10 or larger, so 10 is in the sequence. %Y A080288 Cf. A002858, A080287, A214603, A274522. %K A080288 nonn,more,hard %O A080288 1,2 %A A080288 _Jud McCranie_, Feb 12 2003 %E A080288 23rd term found by _Don Knuth_ - _Jud McCranie_, Aug 22 2008 %E A080288 a(24) on Feb 29 2012; a(25) on Jul 20 2012; and a(26) on Jul 24 2012 found by _Jud McCranie_; %E A080288 a(27) found by Philip Gibbs, Sep 02 2015 %E A080288 a(28) found by Philip Gibbs and _Jud McCranie_, Sep 09 2015 %E A080288 a(29)-a(31) found by Philip Gibbs, Oct 20 2017 %E A080288 Missing a(23) inserted by _Jud McCranie_, Oct 24 2017