A372584 - OEIS

A372584

a(n) = number of odd digits in odd positions in the decimal expansion of n, where position 1 is the least significant digit.

0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2

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OFFSET

0,102

COMMENTS

Corresponds to function a(n) in Borwein and Borwein (1992), p. 622.

First differs from A000035 at n = 100.

LINKS

Paolo Xausa, Table of n, a(n) for n = 0..10000

J. M. Borwein and P. B. Borwein, Strange Series and High Precision Fraud, The American Mathematical Monthly, Vol. 99, No. 7 (1992), pp. 622-640.

FORMULA

Sum_{k >= 0} a(k)/10^k is approximately 10/99 (correct to 99 digits).

MATHEMATICA