login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A005395 Leading term of Stirling's approximation to n!, sqrt(2*Pi)*n^(n+(1/2))/e^n, rounded up. 2

%I

%S 0,1,2,6,24,119,711,4981,39903,359537,3598696,39615626,475687487,

%T 6187239476,86661001741,1300430722200,20814114415224,353948328666101,

%U 6372804626194310,121112786592293964,2422786846761133394,50888617325509644404,1119751494628234263303

%N Leading term of Stirling's approximation to n!, sqrt(2*Pi)*n^(n+(1/2))/e^n, rounded up.

%H G. C. Greubel, <a href="/A005395/b005395.txt">Table of n, a(n) for n = 0..150</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Stirling%27s_approximation">Stirling's Approximation</a>

%F a(n) = ceiling(sqrt(2*Pi)*n^(n+(1/2))/e^n). - _Wesley Ivan Hurt_, Jun 11 2016

%p A005395:=n->ceil(sqrt(2*Pi)*n^(n+(1/2))/exp(1)^n): seq(A005395(n), n=0..30); # _Wesley Ivan Hurt_, Jun 11 2016

%t Table[Ceiling[Sqrt[2*Pi]*n^(n + (1/2))/E^n], {n, 0, 20}] (* _Wesley Ivan Hurt_, Jun 11 2016 *)

%Y Cf. (rounded down) A005393.

%K nonn,easy

%O 0,3

%A _N. J. A. Sloane_

%E a(12) onwards corrected by _Sean A. Irvine_, Jun 11 2016

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 9 01:35 EDT 2020. Contains 336310 sequences. (Running on oeis4.)