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%I #9 Dec 25 2019 08:33:25
%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,
%T 2,2,2,2,2,2,2,2,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
%U 4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5
%N Number of numbers m <= n such that 5 equals the second digit after decimal point of square root of n in decimal representation.
%C For n > 1: if A111862(n)=5 then a(n) = a(n-1) + 1, otherwise a(n) = a(n-1).
%C Lim_{n->infinity} a(n)/n = 1/10.
%D G. Pólya and G. Szegő, Problems and Theorems in Analysis I (Springer 1924, reprinted 1972), Part Two, Chap. 4, Sect. 4, Problem 178.
%e a(10) = 0, a(100) = 5, a(1000) = 79, a(10000) = 934.
%Y Cf. A111862, A111890, A111891, A111892, A111893, A111894, A111896, A111897, A111898, A111899, A111855.
%K nonn,base
%O 1,32
%A _Reinhard Zumkeller_, Aug 20 2005