|
%I #29 Dec 30 2021 07:27:05
%S 1,2,1,2,3,4,3,2,3,4,5,4,5,6,7,8,7,8,7,6,5,4,3,2,3,4,3,4,3,4,5,6,5,4,
%T 3,2,1,2,3,4,5,4,5,6,7,8,9,10,11,12,11,12,11,10,9,10,11,10,11,10,9,10,
%U 11,10,11,10,11,10,11,10,9,8,7,6,5,4,3,2,1,2,3,2,1,0,-1,-2,-1,-2,-3,-4,-3,-2,-3,-4,-3,-2
%N Number of odd digits of Pi minus number of even digits.
%C Cumulative sum of A030657 with zeros replaced by "-1".
%H Zak Seidov, <a href="/A196686/b196686.txt">Table of n, a(n) for n = 1..10000</a> [a(10000) corrected by _Georg Fischer_, Dec 29 2021]
%H Zak Seidov, <a href="https://oeis.org/wiki/File:A196686Fig1.jpg">Dependence a(n) for n = 1..10000</a>
%H Zak Seidov, <a href="https://oeis.org/wiki/File:A196686Fig2.jpg">Dependence a(n) for n = 1..10^6</a>
%e Among first 10 digits of Pi, {3,1,4,1,5,9,2,6,5,3}, there are 7 odd and 3 even, hence a(10)=7-3=4.
%t rd=RealDigits[N[Pi, 10004]][[1]]; a=0; s=Reap[Do[a=a+2Mod[rd[[n]],2]-1; Sow[{n,a}], {n,10004}]][[2,1]] (* this gives b-file *) (* _Zak Seidov_, Oct 05 2011 *)
%Y Cf. A030657, A175792 (negated), A175813 (indices of 0's).
%K sign,base
%O 1,2
%A _Zak Seidov_, Oct 05 2011
%E Definition amended by _Georg Fischer_, Dec 29 2021
|
