This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A102679 #22 Aug 31 2024 19:16:29
%S A102679 0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,1,0,0,0,0,
%T A102679 0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,1,
%U A102679 1,1,1,1,1,1,1,1,1,2,2,2,1,1,1,1,1,1,1,2,2,2,1,1,1,1,1,1,1,2,2,2,0,0,0,0,0
%N A102679 Number of digits >= 7 in decimal representation of n.
%C A102679 a(n) = 0 iff n is in A007093 (numbers in base 7). - _Bernard Schott_, Feb 12 2023
%H A102679 Hieronymus Fischer, <a href="/A102679/b102679.txt">Table of n, a(n) for n = 0..10000</a>
%F A102679 From _Hieronymus Fischer_, Jun 10 2012: (Start)
%F A102679 a(n) = Sum_{j=1..m+1} (floor(n/10^j + 3/10) - floor(n/10^j)), where m = floor(log_10(n)).
%F A102679 G.f.: g(x) = (1/(1-x))*Sum_{j>=0} (x^(7*10^j) - x^(10*10^j))/(1 - x^10^(j+1)). (End)
%p A102679 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]>=7 then ct:=ct+1 else ct:=ct fi od: ct: end: seq(p(n),n=0..125); # _Emeric Deutsch_, Feb 23 2005
%Y A102679 Cf. A007093, A027868, A054899, A055640, A055641, A102669-A102685, A117804, A122840, A122841, A160093, A160094, A196563, A196564. Partial sums see A102680.
%Y A102679 Cf. A000120, A000788, A023416, A059015 (for base 2).
%K A102679 nonn,base,easy
%O A102679 0,78
%A A102679 _N. J. A. Sloane_, Feb 03 2005
%E A102679 More terms from _Emeric Deutsch_, Feb 23 2005