The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A127022 Let f(k) = exp(Pi*sqrt(k)); sequence gives numbers k such that ceiling(f(k)) - f(k) < 1/10^3. 12

%I #24 Sep 08 2022 08:45:29

%S 25,37,43,58,67,74,163,232,522,719,1169,1245,1467,1850,1872,2086,3368,

%T 4075,5773,7685,7802,7942,8325,9728,10032,11682,12158,13574,17908,

%U 18505,19183,19396,20039,20244,20584,22241,23773,23778,23834,25004,27573,28071,32497

%N Let f(k) = exp(Pi*sqrt(k)); sequence gives numbers k such that ceiling(f(k)) - f(k) < 1/10^3.

%H JungHwan Min, <a href="/A127022/b127022.txt">Table of n, a(n) for n = 1..5000</a>

%t a = {}; Do[If[(1 - (Exp[Pi Sqrt[x]] - Floor[Exp[Pi Sqrt[x]]]) > 0) && (1 - ( Exp[Pi Sqrt[x]] - Floor[Exp[Pi Sqrt[x]]])< 10^(-3)), AppendTo[a, x]], {x, 1, 1000}]; a

%t Reap[Block[{$MaxExtraPrecision = Infinity}, Do[If[N[FractionalPart[Exp[Pi Sqrt[n]]], 8] > .999, Sow[n]], {n, 2000}]]][[-1, 1]] (* _JungHwan Min_, Mar 20 2016 *)

%o (PARI) default(realprecision, 500); c(n) = exp(Pi*sqrt(n));

%o for(n=1, 50000, if( ceil(c(n)) - c(n) <1/1000, print1(n", "))) \\ _G. C. Greubel_, Jun 02 2019

%o (Magma) SetDefaultRealField(RealField(500)); R:= RealField(); [n: n in [1..50000] | Ceiling(Exp(Pi(R)*Sqrt(n))) - Exp(Pi(R)*Sqrt(n)) lt 1/1000]; // _G. C. Greubel_, Jun 02 2019

%Y Cf. A035484, A127023, A127024, A127025.

%K nonn

%O 1,1

%A _Artur Jasinski_, Jan 03 2007

%E a(16)-a(43) added (from _JungHwan Min_'s b-file) by _Jon E. Schoenfield_, Sep 04 2017

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 4 19:35 EDT 2024. Contains 373102 sequences. (Running on oeis4.)