%I #19 Dec 23 2022 09:11:38
%S 0,1,2,3,4,5,7,8,9,10,11,13,15,16,17,18,20,21,23,24,25,27,29,30,32,33,
%T 35,36,37,38,40,42,44,46,47,48,51,52,53,54,55,57,60,61,63,64,66,67,70,
%U 71,72,74,76,77,79,81,83,84,85,86,88,90,92,94,96,97,101,102,103,104,105
%N a(n) = Sum_{k>=0} floor(n/(5*k + 1)).
%C Partial sums of A001876.
%H Seiichi Manyama, <a href="/A218444/b218444.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = Sum_{k>=0} floor(n/(5*k + 1)).
%t a[n_] := Sum[ Floor[n/(5*k+1)], {k, 0, Ceiling[n/5]}]; Table[a[n], {n, 0, 70}] (* _Jean-François Alcover_, Feb 22 2013 *)
%o (PARI) a(n)=sum(k=0,n,(n\(5*k+1)))
%o (Maxima) A218444[n]:=sum(floor(n/(5*k+1)),k,0,n)$
%o makelist(A218444[n],n,0,80); /* _Martin Ettl_, Oct 29 2012 */
%Y Cf. A218444, A218445, A218446.
%K nonn
%O 0,3
%A _Benoit Cloitre_, Oct 28 2012