OFFSET
1,1
COMMENTS
The numbers formed in this sequence are 1,2,3,4,5,6,9. Conjecture: The terms of this sequence are nonrepeating and nonterminating.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..5000
A. Frank and P. Jacqueroux, International contest, (2001) Sequence 26. [From R. J. Mathar, Feb 23 2009]
FORMULA
Let the i-th digit of Pi be the digit of Pi in the i-th position. Then the Pi-th digit of Pi is the digit of Pi in the position corresponding to the value of the i-th digit.
EXAMPLE
The digit of Pi in the first position is 3, and the digit of Pi in the third position is 4, the first term in the table.
MATHEMATICA
id = RealDigits[Pi, 10, 105][[1]]; id[[0]] = 3; Table[id[[id[[n]] ]], {n, 105}] (* Robert G. Wilson v, Mar 17 2009 *)
PROG
(PARI) g(n)=a=Vec(Str(Pi*10^9990)); for(x=1, n, v=eval(a[x]); if(v==0, print1(a[v+10]", "), print1(a[v]", ")))
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Cino Hilliard, May 27 2006
EXTENSIONS
Missing terms a(33), a(55) and a(66) inserted by R. J. Mathar, Feb 23 2009
STATUS
approved