login
Greatest integer k such that k/2^n < 1/e.
3

%I #5 Oct 11 2017 09:15:35

%S 0,0,1,2,5,11,23,47,94,188,376,753,1506,3013,6027,12054,24109,48218,

%T 96437,192874,385749,771499,1542998,3085996,6171992,12343985,24687971,

%U 49375942,98751885,197503771,395007542,790015084,1580030168,3160060337,6320120674

%N Greatest integer k such that k/2^n < 1/e.

%H Clark Kimberling, <a href="/A293339/b293339.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = floor(r*2^n), where r = 1/e.

%F a(n) = A293340(n) - 1.

%t z = 120; r = 1/E;

%t Table[Floor[r*2^n], {n, 0, z}]; (* A293339 *)

%t Table[Ceiling[r*2^n], {n, 0, z}]; (* A293340 *)

%t Table[Round[r*2^n], {n, 0, z}]; (* A293341 *)

%Y Cf. A001113, A027437, A293340, A293341.

%K nonn,easy

%O 0,4

%A _Clark Kimberling_, Oct 10 2017