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 A002097 #15 Oct 06 2017 17:16:22 %S A002097 1,2,4,6,11,20,29 %N A002097 Numbers that are not the sum of 3 nonzero triangular numbers. %C A002097 A063993(a(n)) = 0. - _Reinhard Zumkeller_, Jul 20 2012 %t A002097 Complement[Range[30],Union[Total/@Tuples[Accumulate[Range[8]],3]]] (* _Harvey P. Dale_, Oct 06 2017 *) %Y A002097 Cf. A111638, A064825. %K A002097 fini,full,nonn %O A002097 1,2 %A A002097 _N. J. A. Sloane_, _Dan Hoey_