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A111855 Number of numbers m <= n such that 5 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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 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, 5, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,31

COMMENTS

For n > 1: if A023961(n)=5 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..105.

EXAMPLE

a(10) = 0, a(100) = 7, a(1000) = 93, a(10000) = 970.

CROSSREFS

Cf. A111850, A111851, A111852, A111853, A111854, A111856, A111857, A111858, A111859, A111895.

Sequence in context: A105209 A179076 A095861 * A071701 A064459 A279758

Adjacent sequences:  A111852 A111853 A111854 * A111856 A111857 A111858

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Aug 20 2005

STATUS

approved

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Last modified April 1 07:29 EDT 2020. Contains 333155 sequences. (Running on oeis4.)