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 A102669 Number of digits >= 2 in decimal representation of n. 30
 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,23 LINKS Hieronymus Fischer, Table of n, a(n) for n = 0..10000 FORMULA Contribution from Hieronymus Fischer, Jun 10 2012: (Start) a(n) = Sum_{j=1..m+1} (floor(n/10^j + 4/5) - floor(n/10^j)), where m = floor(log_10(n)). G.f.: g(x) = (1/(1-x))*Sum_{j>=0} (x^(2*10^j) - x^(10*10^j))/(1 - x^10^(j+1)). General formulas for the number of digits >= d in the decimal representations of n, where 1 <= d <= 9: a(n) = Sum_{j=1..m+1} (floor(n/10^j + (10-d)/10) - floor(n/10^j)), where m = floor(log_10(n)). G.f.: g(x) = (1/(1-x))*sum_{j>=0} (x^(d*10^j) - x^(10*10^j))/(1 - x^10^(j+1)). (End) MAPLE 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]>=2 then ct:=ct+1 else ct:=ct fi od: ct: end: seq(p(n), n=0..116); # Emeric Deutsch, Feb 23 2005 MATHEMATICA Table[Total@ Take[DigitCount@ n, {2, 9}], {n, 0, 104}] (* Michael De Vlieger, Aug 17 2017 *) CROSSREFS Cf. A027868, A054899, A055640, A055641, A102670 - A102685, A117804, A122840, A122841, A160093, A160094, A196563, A196564. Partial sums see A102670. Cf. A000120, A000788, A023416, A059015 (for base 2). Sequence in context: A194322 A052010 A138471 * A248327 A055098 A297035 Adjacent sequences:  A102666 A102667 A102668 * A102670 A102671 A102672 KEYWORD nonn,base,easy AUTHOR N. J. A. Sloane, Feb 03 2005 EXTENSIONS More terms from Emeric Deutsch, Feb 23 2005 STATUS approved

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Last modified November 26 05:48 EST 2022. Contains 358353 sequences. (Running on oeis4.)