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 A060773 #9 Aug 11 2025 10:21:03
%S A060773 0,1,2,4,5,8,11,14,20,29,50,53
%N A060773 Numbers having a unique partition into three nonnegative triangular numbers.
%t A060773 trig[n_]:=n(n+1)/2; trigInv[x_]:=Ceiling[Sqrt[Max[0, 2x]]]; lim=100; nLst=Table[0, {trig[lim]}]; Do[n=trig[a]+trig[b]+trig[c]; If[n>0 && n<=trig[lim], nLst[[n]]++ ], {a, 0, lim}, {b, a, trigInv[trig[lim]-trig[a]]}, {c, b, trigInv[trig[lim]-trig[a]-trig[b]]}]; Flatten[Position[nLst, 1]] (* _T. D. Noe_, Aug 10 2005 *)
%Y A060773 Cf. A000217, A061262, A053614.
%Y A060773 Cf. A111638 (n having a unique partition into three positive triangular numbers).
%K A060773 nonn,fini,full
%O A060773 0,3
%A A060773 _Erich Friedman_, Apr 24 2001