A235037 - OEIS

%I #8 Jan 07 2014 04:27:23

%S 1,2,2,2,2,3,3,3,3,3,3,3,3,3,4,4,4,4,4,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,

%T 6,6,6,6,6,6,6,7,7,7,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,9,9,9,

%U 9,9,9,9,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10

%N Number of terms of A014847 that are not greater than n.

%H Bruno Berselli, <a href="/A235037/b235037.txt">Table of n, a(n) for n = 1..2000</a>

%e a(6)=3 because the terms of A014847 not greater than 6 are 1,2,6.

%e a(17)=4 because the terms of A014847 not greater than 17 are 1,2,6,15.

%t a[n_] := Module[{ris}, ris = {}; Do[If[Mod[Binomial[2 k, k], k] == 0, AppendTo[ris, k]], {k, n}]; Length[ris]]; Table[a[n], {n, 100}]

%Y Cf. A014847.

%K nonn

%O 1,2

%A _Bruno Berselli_, Jan 05 2014 - sequence suggested by Umberto Cerruti (University of Turin, Italy)