A194227 - OEIS

%I #7 Dec 12 2024 11:39:08

%S 0,0,1,1,2,3,3,3,3,4,4,5,6,6,6,6,7,7,8,9,9,9,9,10,10,11,12,12,12,12,

%T 13,13,14,15,15,15,15,16,16,17,18,18,18,18,19,19,20,21,21,21,21,22,22,

%U 23,24,24,24,24,25,25,26,27,27,27,27,28,28,29,30,30,30,30,31,31

%N [sum{(2k/7) : 1<=k<=n}], where [ ]=floor, ( )=fractional part.

%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 0, 0, 0, 0, 1, -1).

%t r = 2/7;

%t a[n_] := Floor[Sum[FractionalPart[k*r], {k, 1, n}]]

%t Table[a[n], {n, 1, 90}]    (* A194227 *)

%t s[n_] := Sum[a[k], {k, 1, n}]

%t Table[s[n], {n, 1, 100}]   (* A194228 *)

%Y Cf. A194227.

%K nonn

%O 1,5

%A _Clark Kimberling_, Aug 19 2011