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A011533 Numbers that contain a 3. 22
3, 13, 23, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 43, 53, 63, 73, 83, 93, 103, 113, 123, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 143, 153, 163, 173, 183, 193, 203, 213, 223, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 243, 253 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

James Grime and Brady Haran, 3 is everywhere, Numberphile video

Index entries for 10-automatic sequences.

FORMULA

a(n) ~ n. - Charles R Greathouse IV, Aug 28 2012

For m >= 1, a(10^m - 9^m) = 10^m-7, a(10^m - 9^m + 1) = 10^m + 3. - Robert Israel, Jan 11 2016

MAPLE

M:= 3: # to get all terms of up to M digits

B:= {3}: A:= {3}:

for i from 2 to M do

   B:= map(t -> seq(10*t+j, j=0..9), B) union

      {seq(10*x+3, x=10^(i-2)..10^(i-1)-1)}:

   A:= A union B;

od:

sort(convert(A, list)); # Robert Israel, Jan 11 2016

MATHEMATICA

Select[Range[600] - 1, DigitCount[#, 10, 3]>0 &] (* Vincenzo Librandi, Jan 11 2016 *)

PROG

(Haskell)

a011533 n = a011533_list !! (n-1)

a011533_list = filter ((elem '3') . show) [0..]

-- Reinhard Zumkeller, Apr 10 2015

(MAGMA) [n: n in [0..500] | 3 in Intseq(n)]; // Vincenzo Librandi, Jan 11 2016

(PARI) isok(n)=my(d=digits(n)); for (k=1, #d, if (d[k] == 3, return (1))); \\ Michel Marcus, Jan 11 2016

CROSSREFS

Complement: A052405.

Cf. A016189.

Sequence in context: A180970 A135580 A166566 * A277965 A043501 A277590

Adjacent sequences:  A011530 A011531 A011532 * A011534 A011535 A011536

KEYWORD

nonn,base,easy,changed

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified June 23 21:09 EDT 2018. Contains 311812 sequences. (Running on oeis4.)