A011546 Decimal expansion of Pi rounded to n places.

3, 31, 314, 3142, 31416, 314159, 3141593, 31415927, 314159265, 3141592654, 31415926536, 314159265359, 3141592653590, 31415926535898, 314159265358979, 3141592653589793, 31415926535897932, 314159265358979324, 3141592653589793238, 31415926535897932385, 314159265358979323846

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy
• base

Comments

Scherzer (2012) writes: "The 17th-most common 10-digit password is 3141592654 (for you non-math nerds, those are the first [ten] digits of Pi)." The information comes from an analysis of expired ATM PIN codes conducted by Nick Berry of Data Genetics. - Alonso del Arte, Sep 21 2012

Examples

			a(4) = floor(10^4 * Pi + 0.5) = 31416.
		

Links

• Paolo Xausa, Table of n, a(n) for n = 0..995
• Mohammad K. Azarian, Al-Risala al-Muhitiyya: A Summary, (The Treatise on the Circumference), Missouri Journal of Mathematical Sciences, Vol. 22, No. 2, 2010, pp. 64-85.
• Lisa Scherzer, "Cracking Your PIN Code: Easy as 1-2-3-4", The Exchange, Sep 21 2012.

Crossrefs

Cf. A000796, A011552, A011544, A011548.

Programs

Maple

a:= proc(n) Digits:= n+20;
       round(10^n * Pi)
    end:
seq(a(n), n=0..20); # Alois P. Heinz, Mar 11 2016

Mathematica

Module[{nn=20,pid},pid=RealDigits[Pi,10,nn+2][[1]];Table[Floor[ (FromDigits[ Take[pid,n+1]])/10+1/2],{n,nn}]] (* Harvey P. Dale, Oct 09 2017 *)
Round[Pi*10^Range[0, 20]] (* Paolo Xausa, Jul 08 2025 *)

PARI

a(n)=round(Pi*10^n) \\ Charles R Greathouse IV, Sep 21 2012

Formula

a(n) = floor(10^n * Pi + 0.5).