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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; internal format)
OFFSET

1,17

COMMENTS

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

a(n)/n --> 1/10.

REFERENCES

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

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 A059995

Adjacent sequences:  A111848 A111849 A111850 * A111852 A111853 A111854

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Aug 20 2005

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Last modified February 15 15:20 EST 2012. Contains 205823 sequences.