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

Offset

0,1

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

Links

Table of n, a(n) for n=0..19.

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

Formula

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

Example

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

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 *)

Prog

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

Crossrefs

Sequence in context: A247351 A089289 A011545 * A361612 A276195 A210852

Adjacent sequences: A011543 A011544 A011545 * A011547 A011548 A011549

Keyword

nonn,base

Author

N. J. A. Sloane

Status

approved