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A196686 Number of odd digits of Pi minus number of even digits. 2
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, 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, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Cumulative sum of A030657 with zeros replaced by "-1".
LINKS
Zak Seidov, Table of n, a(n) for n = 1..10000 [a(10000) corrected by Georg Fischer, Dec 29 2021]
EXAMPLE
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.
MATHEMATICA
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 *)
CROSSREFS
Cf. A030657, A175792 (negated), A175813 (indices of 0's).
Sequence in context: A202275 A030307 A175792 * A213088 A357564 A169809
KEYWORD
sign,base
AUTHOR
Zak Seidov, Oct 05 2011
EXTENSIONS
Definition amended by Georg Fischer, Dec 29 2021
STATUS
approved

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Last modified May 27 19:58 EDT 2024. Contains 372882 sequences. (Running on oeis4.)