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A102671 Number of digits >= 3 in decimal representation of n.

%I A102671 #25 Nov 20 2022 08:45:12
%S A102671 0,0,0,1,1,1,1,1,1,1,0,0,0,1,1,1,1,1,1,1,0,0,0,1,1,1,1,1,1,1,1,1,1,2,
%T A102671 2,2,2,2,2,2,1,1,1,2,2,2,2,2,2,2,1,1,1,2,2,2,2,2,2,2,1,1,1,2,2,2,2,2,
%U A102671 2,2,1,1,1,2,2,2,2,2,2,2,1,1,1,2,2,2,2,2,2,2,1,1,1,2,2,2,2,2,2,2,0,0,0,1,1
%N A102671 Number of digits >= 3 in decimal representation of n.
%C A102671 a(n) = 0 iff n is in A007089 (numbers in base 3). - _Bernard Schott_, Nov 20 2022
%H A102671 Hieronymus Fischer, <a href="/A102671/b102671.txt">Table of n, a(n) for n = 0..10000</a>
%F A102671 From _Hieronymus Fischer_, Jun 10 2012: (Start)
%F A102671 a(n) = Sum_{j=1..m+1} (floor((n/10^j) + 7/10) - floor(n/10^j)), where m = floor(log_10(n)).
%F A102671 G.f.: g(x) = (1/(1-x))*Sum_{j>=0} (x^(3*10^j) - x^(10*10^j))/(1 - x^10^(j+1)). (End)
%p A102671 p:=proc(n) local b,ct,j: b:=convert(n,base,10): ct:=0: for j from 1 to nops(b) do if b[j]>=3 then ct:=ct+1 else ct:=ct fi od: ct: end: seq(p(n),n=0..116); # _Emeric Deutsch_, Feb 23 2005
%t A102671 Table[Count[IntegerDigits[n],_?(#>2&)],{n,0,110}] (* _Harvey P. Dale_, Mar 07 2012 *)
%Y A102671 Cf. A007089, A027868, A054899, A055640, A055641, A102669-A102685, A117804, A122840, A122841, A160093, A160094, A196563, A196564. Partial sums see A102672.
%Y A102671 Cf. A000120, A000788, A023416, A059015 (for base 2).
%K A102671 nonn,base,easy
%O A102671 0,34
%A A102671 _N. J. A. Sloane_, Feb 03 2005
%E A102671 More terms from _Emeric Deutsch_, Feb 23 2005