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 A047784 #13 Sep 08 2022 08:44:57
%S A047784 1,2,3,4,4,5,5,6,6,7,7,7,8,8,9,9,9,10,10,10,11,11,11,12,12,12,12,13,
%T A047784 13,13,14,14,14,14,15,15,15,16,16,16,16,17,17,17,17,18,18,18,18,19,19,
%U A047784 19,19,20,20,20,20,21,21,21,21,22,22,22,22,23,23,23,23
%N A047784 Nearest integer to Li(n).
%D A047784 M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 238.
%H A047784 G. C. Greubel, <a href="/A047784/b047784.txt">Table of n, a(n) for n = 2..10000</a>
%H A047784 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%F A047784 a(n) = round(logarithmic integral(n)). - _G. C. Greubel_, May 16 2019
%t A047784 Table[Round[LogIntegral[n]], {n, 2, 80}] (* _G. C. Greubel_, May 16 2019 *)
%o A047784 (PARI) vector(80, n, n++; round(real(-eint1(-log(n)))) ) \\ _G. C. Greubel_, May 16 2019
%o A047784 (Magma) [Round(LogIntegral(n)): n in [2..80]]; // _G. C. Greubel_, May 16 2019
%o A047784 (Sage) [round(li(n)) for n in (2..80)] # _G. C. Greubel_, May 16 2019
%Y A047784 Cf. A047783 (floor), A047785 (ceiling).
%K A047784 nonn
%O A047784 2,2
%A A047784 _N. J. A. Sloane_