Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I M2208 #61 Oct 03 2022 11:59:20
%S 3,1,1,0,3,7,5,5,2,4,2,1,0,2,6,4,3,0,2,1,5,1,4,2,3,0,6,3,0,5,0,5,6,0,
%T 0,6,7,0,1,6,3,2,1,1,2,2,0,1,1,1,6,0,2,1,0,5,1,4,7,6,3,0,7,2,0,0,2,0,
%U 2,7,3,7,2,4,6,1,6,6,1,1,6,3,3,1,0,4,5,0,5,1,2,0,2,0,7,4,6,1,6,1,5,0,0,2,3
%N Expansion of Pi in base 8.
%D D. E. Knuth, The Art of Computer Programming. Addison-Wesley, Reading, MA, Vol. 1, p. 614.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H G. C. Greubel, <a href="/A006941/b006941.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%F a(n) = 4*A004601(3n) + 2*A004601(3n+1) + 1*A004601(3n+2). - _Jason Kimberley_, Nov 06 2012
%e 3.1103755242102643021514230630505600670...
%p convert(evalf(Pi), octal, 120); # _Alois P. Heinz_, Dec 16 2018
%t RealDigits[ N[ Pi, 105], 8] [[1]]
%t Table[ResourceFunction["NthDigit"][Pi, n, 8], {n, 1, 105}] (* _Joan Ludevid_, Sep 13 2022; easy to compute a(10000000)=1 with this function; requires Mathematica 12.0+ *)
%Y Pi in base b: A004601 (b=2), A004602 (b=3), A004603 (b=4), A004604 (b=5), A004605 (b=6), A004606 (b=7), this sequence (b=8), A004608 (b=9), A000796 (b=10), A068436 (b=11), A068437 (b=12), A068438 (b=13), A068439 (b=14), A068440 (b=15), A062964 (b=16), A060707 (b=60).
%Y Cf. A007514.
%K nonn,base,cons,easy
%O 1,1
%A _N. J. A. Sloane_
%E More terms from _Michel ten Voorde_, Apr 14 2001