A111898 Number of numbers m <= n such that 8 equals the second digit after decimal point of square root of n in decimal representation.

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, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 13, 13, 13, 13, 13

Offset

1,29

Comments

For n > 1: if A111862(n)=8 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..94.

Example

a(10) = 0, a(100) = 13, a(1000) = 94, a(10000) = 1002.

Crossrefs

Cf. A111890, A111891, A111892, A111893, A111894, A111895, A111896, A111897, A111899, A111858.

Sequence in context: A279223 A214956 A209899 * A279041 A072746 A179528

Adjacent sequences: A111895 A111896 A111897 * A111899 A111900 A111901

Keyword

nonn,base

Author

Reinhard Zumkeller, Aug 20 2005

Status

approved