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 A257023 #4 Apr 15 2015 15:43:43 %S A257023 1,1,1,2,1,2,1,2,2,1,2,2,1,2,2,3,1,2,2,3,1,2,2,3,2,1,2,2,3,2,1,2,2,3, %T A257023 2,3,1,2,2,3,2,3,1,2,2,3,2,3,2,1,2,2,3,2,3,2,1,2,2,3,2,3,2,3,1,2,2,3, %U A257023 2,3,2,3,1,2,2,3,2,3,2,3,3,1,2,2,3,2 %N A257023 Number of terms in the quarter-sum representation of n. %C A257023 Every positive integer is a sum of at most four distinct quarter squares, of which the least term is the trace; see A257019. %H A257023 Clark Kimberling, <a href="/A257023/b257023.txt">Table of n, a(n) for n = 0..1000</a> %e A257023 Quarter-square representations: %e A257023 r(0) = 0, so a(0) = 1 %e A257023 r(3) = 2 + 1, so a(3) = 2 %t A257023 z = 100; b[n_] := Floor[(n + 1)^2/4]; bb = Table[b[n], {n, 0, 100}]; %t A257023 s[n_] := Table[b[n], {k, b[n + 1] - b[n]}]; %t A257023 h[1] = {1}; h[n_] := Join[h[n - 1], s[n]]; %t A257023 g = h[200]; r[0] = {0}; %t A257023 r[n_] := If[MemberQ[bb, n], {n}, Join[{g[[n]]}, r[n - g[[n]]]]]; %t A257023 Table[Length[r[n]], {n, 0, 3 z}] (* A257022 *) %Y A257023 Cf. A002620, A257019, A257020, A257021, A257022. %K A257023 nonn,easy %O A257023 0,4 %A A257023 _Clark Kimberling_, Apr 15 2015