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A111854 Number of numbers m <= n such that 4 equals the first digit after decimal point of square root of n in decimal representation. 11
0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 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, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 13, 13, 13, 13 (list; graph; refs; listen; history; internal format)
OFFSET

1,6

COMMENTS

For n>1: if A023961(n)=4 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) = 2, a(100) = 13, a(1000) = 112, a(10000) = 1030.

CROSSREFS

Cf. A111850, A111851, A111852, A111853, A111855, A111856, A111857, A111858, A111859, A111894.

Sequence in context: A056556 A111651 A151982 * A132085 A111654 A067099

Adjacent sequences:  A111851 A111852 A111853 * A111855 A111856 A111857

KEYWORD

nonn,base

AUTHOR

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

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Last modified February 17 13:02 EST 2012. Contains 206021 sequences.