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 A327672 #40 Dec 26 2023 08:32:08 %S A327672 0,1,3,5,7,10,13,16,19,22,26,30,34,38,42,46,50,55,60,65,70,75,80,85, %T A327672 90,95,101,107,113,119,125,131,137,143,149,155,161,168,175,182,189, %U A327672 196,203,210,217,224,231,238,245,252,260,268,276,284,292,300,308,316 %N A327672 a(n) = Sum_{k=0..n} ceiling(sqrt(k)). %C A327672 Partial sums of A003059. %C A327672 Given a digraph whose vertices are numbered from 0 to n and in which an edge (u,v) exists iff u < v, a(n) is the maximum number of arcs that can be chosen so that for each vertex j other than 0 and n, the number of chosen arcs whose tail is vertex j equals the number of chosen arcs whose head is vertex j. - _Xutong Ding_, Dec 12 2023 %H A327672 Peter Kagey, <a href="/A327672/b327672.txt">Table of n, a(n) for n = 0..10000</a> %F A327672 a(n) = (1 + floor(sqrt(n)))*(6*n - floor(sqrt(n)) - 2*floor(sqrt(n))^2)/6. - _Vaclav Kotesovec_, Dec 26 2023 %t A327672 Accumulate[Ceiling[Sqrt[Range[0, 60]]]] %t A327672 Table[(1 + Floor[Sqrt[n]])*(6*n - Floor[Sqrt[n]] - 2*Floor[Sqrt[n]]^2)/6, {n, 0, 100}] (* _Vaclav Kotesovec_, Dec 26 2023 *) %Y A327672 Cf. A003059, A022554. %K A327672 nonn %O A327672 0,3 %A A327672 _Peter Kagey_, Sep 21 2019