login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

a(n) = floor(sqrt( 2*Pi )^n).
4

%I #11 Feb 01 2022 01:21:53

%S 1,2,6,15,39,98,248,621,1558,3906,9792,24546,61528,154230,386597,

%T 969056,2429063,6088760,15262258,38256809,95895600,240374623,

%U 602529828,1510318305,3785806567,9489609784,23786924200,59624976768,149457652641,374634777972

%N a(n) = floor(sqrt( 2*Pi )^n).

%H T. D. Noe, <a href="/A001674/b001674.txt">Table of n, a(n) for n = 0..500</a>

%H <a href="/index/Pow#POWERS">OEIS index entries related to powers of irrational constants</a>.

%t Table[Floor[Sqrt[2*Pi]^n], {n, 0, 50}] (* _T. D. Noe_, Aug 09 2012 *)

%o (PARI) a(n)=(2*Pi)^(n/2)\1 \\ _M. F. Hasler_, May 29 2018

%Y Cf. A001674 (ceiling sqrt(2 Pi)^n), A017910 (floor sqrt(2)^n), A000149 (floor e^n), A001672 (floor Pi^n), A062541 (floor (Pi*e)^n), A121831 (floor (Pi+e)^n), A032739 (floor (Pi/e)^n), A014217 (floor ((1+sqrt(5))/2)^n).

%K nonn

%O 0,2

%A _N. J. A. Sloane_

%E Edited by _M. F. Hasler_, May 29 2018