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 A111897 Number of numbers m <= n such that 7 equals the second 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, 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, 3, 3, 3, 3, 3, 3, 3, 3, 3, 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, 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, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,20 COMMENTS For n > 1: if A111862(n)=7 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 EXAMPLE a(10) = 0, a(100) = 7, a(1000) = 100, a(10000) = 1000. MATHEMATICA Accumulate[Table[If[Mod[IntegerPart[100*Sqrt[n]], 10]==7, 1, 0], {n, 110}]] (* Harvey P. Dale, Oct 16 2014 *) CROSSREFS Cf. A111862, A111890, A111891, A111892, A111893, A111894, A111895, A111896, A111898, A111899, A111857. Sequence in context: A329199 A262303 A127321 * A185711 A185712 A328499 Adjacent sequences:  A111894 A111895 A111896 * A111898 A111899 A111900 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Aug 20 2005 STATUS approved

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Last modified November 30 06:11 EST 2020. Contains 338781 sequences. (Running on oeis4.)