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%I #5 Feb 01 2022 18:50:22
%S 10,7,5,50,44,40,37,35,333,316,301,288,277,267,258,2500,2425,2357,
%T 2294,2236,2182,2132,2085,2041,20000,19611,19245,18898,18569,18257,
%U 17960,17677,17407,17149,16903,166666,164398,162221,160128,158113,156173
%N Integer part of square root of the reciprocal of a number multiplied by 10 to the power of the integer part of the square root of the number.
%C The sum of the reciprocals = 0.595091701724608076103001212.. Converges rapidly.
%F floor( sqrt(1/x)*10^(floor(sqrt(x))) )
%t Table[Floor[Sqrt[1/x] 10^Floor[Sqrt[x]]],{x,50}] (* _Harvey P. Dale_, Feb 01 2022 *)
%o (PARI) rootrecip(n) = { sr=0; for(x=1,n, r =sqrt(x); ip=floor(r); fp=r-ip; y=floor((1/r)*10^ip); print1(y","); sr = sr + 1.0/y; ); print(); print(sr) }
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Dec 11 2003