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A111892 Number of numbers m <= n such that 2 equals the second digit after decimal point of square root of n in decimal representation. 11
0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,17

COMMENTS

For n>1: if A111862(n)=2 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.

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

a(10) = 1, a(100) = 7, a(1000) = 95, a(10000) = 1000.

CROSSREFS

Cf. A111890, A111891, A111893, A111894, A111895, A111896, A111897, A111898, A111899, A111852.

Sequence in context: A111891 A296076 A086858 * A108248 A087104 A069926

Adjacent sequences:  A111889 A111890 A111891 * A111893 A111894 A111895

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, Aug 20 2005

STATUS

approved

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Last modified October 23 08:57 EDT 2019. Contains 328345 sequences. (Running on oeis4.)