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%I #4 Jan 28 2023 12:35:44
%S 0,0,0,2,4,6,8,11,14,18,21,25,29,33,38,43,48,53,58,63,69,75,81,87,93,
%T 100,106,113,120,127,134,141,149,156,164,172,180,188,196,204,212,221,
%U 230,238,247,256,265,275,284,294,303,313,322,332,342,352,363,373
%N a(n) = greatest integer k such that (n+k)^2 <= n^3.
%F a(n) = -n + [n^(3/2)], where [ ] = floor.
%e a(7) = 11 because (7+11)^2 <= 7^3 < (7+12)^2.
%t a[n_] := Select[-1 + Range[1300], (n + #)^2 <= n^3 < (n + # + 1)^2 &]
%t Flatten[Table[a[n], {n, 0, 100}]]
%Y Cf. A000290, A000578.
%K nonn
%O 0,4
%A _Clark Kimberling_, Jan 26 2023