%I #26 Sep 08 2022 08:44:37
%S 2,12,20,21,22,23,24,25,26,27,28,29,32,42,52,62,72,82,92,102,112,120,
%T 121,122,123,124,125,126,127,128,129,132,142,152,162,172,182,192,200,
%U 201,202,203,204,205,206,207,208,209,210,211,212,213,214
%N Numbers that contain a 2.
%H Reinhard Zumkeller, <a href="/A011532/b011532.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F a(n) ~ n. - _Charles R Greathouse IV_, Feb 12 2017
%t Select[Range[600] - 1, DigitCount[#, 10, 2]>0 &] (* _Vincenzo Librandi_, Jan 11 2016 *)
%o (Haskell)
%o a011532 n = a011532_list !! (n-1)
%o a011532_list = filter ((elem '2') . show) [0..]
%o -- _Reinhard Zumkeller_, Apr 10 2015
%o (Magma) [n: n in [0..500] | 2 in Intseq(n)]; // _Vincenzo Librandi_, Jan 11 2016
%o (GAP) Filtered([1..220],n->2 in ListOfDigits(n)); # _Muniru A Asiru_, Feb 23 2019
%Y Numbers that contain a digit k: A011531 (k=1), A011533 (k=3), A011534 (k=4), A011535 (k=5), A011536 (k=6), A011537 (k=7), A011538 (k=8), A011539 (k=9), A011540 (k=0).
%K nonn,base,easy
%O 1,1
%A _N. J. A. Sloane_
|