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 A184977 #23 Aug 28 2025 05:29:37 %S A184977 0,1,2,4,6,9,13,17,22,27,33,39,46,54,62,71,80,90,100,111,123,135,148, %T A184977 161,175,190,205,221,237,254,271,289,308,327,347,367,388,409,431,454, %U A184977 477,501,525,550,575,601,628,655,683,711,740,770,800,831,862,894,926,959,993,1027,1062 %N A184977 a(n) = Sum_{k=1..n} floor(k*gamma) where gamma is Euler's constant (A001620). %C A184977 a(n) = A183143(n) for n = 1..96 where A183143(n) is the sequence floor(1/r) + floor(2/r) + ... + floor(n/r) and r = sqrt(3). It is interesting to note that a(n)/n^2 converges to gamma/2. %C A184977 gamma = 0.57721566490153286060651209... (A002852) %C A184977 1/sqrt(3) = 0.577350269189625764509148... (A020760) %C A184977 Starts to differ from A183143 at a(97). - _R. J. Mathar_, Aug 28 2025 %H A184977 G. C. Greubel, <a href="/A184977/b184977.txt">Table of n, a(n) for n = 1..5000</a> %F A184977 Partial sums of A038128. %p A184977 with(numtheory):Digits:=500:s:=0:c:=evalf(gamma(0)):for n from 1 to 100 do: %p A184977 s:=s+floor(n*c):printf(`%d, `,s):od: %t A184977 Table[Sum[Floor[k*EulerGamma], {k, 1, n}], {n, 50}] (* _G. C. Greubel_, Jun 02 2017 *) %o A184977 (PARI) a(n) = sum(k=1, n, floor(k*Euler)); \\ _Michel Marcus_, Apr 02 2017 %o A184977 (Magma) R:=RealField(100); [(&+[Floor(k*EulerGamma(R)): k in [1..n]]): n in [1..50]]; // _G. C. Greubel_, Aug 27 2018 %Y A184977 Cf. A001620, A038128. %K A184977 nonn,changed %O A184977 1,3 %A A184977 _Michel Lagneau_, Mar 27 2011 %E A184977 Name edited by _Jon E. Schoenfield_, Apr 02 2017