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
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
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
KEYWORD
nonn,base
AUTHOR
STATUS
approved