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A111851 Number of numbers m <= n such that 1 equals the first digit after decimal point of square root of n in decimal representation. 11
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,17

COMMENTS

For n > 1: if A023961(n)=1 then a(n) = a(n-1) + 1, otherwise a(n) = a(n-1).

Lim_{n->infinity} a(n)/n = 1/10.

REFERENCES

G. Pólya and G. Szegő, Problems and Theorems in Analysis I (Springer 1924, reprinted 1972), Part Two, Chap. 4, Sect. 4, Problem 178.

LINKS

Table of n, a(n) for n=1..104.

EXAMPLE

a(10) = 1, a(100) = 9, a(1000) = 99, a(10000) = 990.

CROSSREFS

Cf. A111850, A111852, A111853, A111854, A111855, A111856, A111857, A111858, A111859, A111891.

Sequence in context: A135665 A135662 A111853 * A111852 A133880 A226233

Adjacent sequences:  A111848 A111849 A111850 * A111852 A111853 A111854

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Aug 20 2005

STATUS

approved

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Last modified March 2 09:45 EST 2021. Contains 341746 sequences. (Running on oeis4.)