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 A109303 #34 Feb 18 2024 08:26:52 %S A109303 11,22,33,44,55,66,77,88,99,100,101,110,111,112,113,114,115,116,117, %T A109303 118,119,121,122,131,133,141,144,151,155,161,166,171,177,181,188,191, %U A109303 199,200,202,211,212,220,221,222,223,224,225,226,227,228,229,232,233,242 %N A109303 Numbers k with at least one duplicate base-10 digit (A107846(k) > 0). %C A109303 Complement of A010784, numbers with distinct base-10 digits, so all numbers greater than 9876543210 (last term of A010784) are terms. a(263)=1001 is the first term not also a term of A044959; a(264)=1002 is the first term not also a term of A084050. The terms of A044959 greater than 9 are a subsequence. The terms of A084050 greater than 90 are a subsequence. %C A109303 A178788(a(n)) = 0; A178787(a(n)) = A178787(a(n)-1); A043537(a(n)) < A109303(a(n)). - _Reinhard Zumkeller_, Jun 30 2010 %C A109303 A227362(a(n)) < a(n). - _Reinhard Zumkeller_, Jul 09 2013 %H A109303 Reinhard Zumkeller, <a href="/A109303/b109303.txt">Table of n, a(n) for n = 1..10000</a> %H A109303 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1). %t A109303 Select[Range[300], Max[DigitCount[#]] > 1 &] (* _Harvey P. Dale_, Jan 14 2011 *) %o A109303 (Haskell) %o A109303 a109303 n = a109303_list !! (n-1) %o A109303 a109303_list = filter ((> 0) . a107846) [0..] %o A109303 -- _Reinhard Zumkeller_, Jul 09 2013 %o A109303 (Python) %o A109303 def ok(n): s = str(n); return len(set(s)) < len(s) %o A109303 print([k for k in range(243) if ok(k)]) # _Michael S. Branicky_, Nov 22 2021 %Y A109303 Cf. A010784 (numbers with distinct digits), A044959 (numbers with no two equally numerous digits), A084050 (numbers with a palindromic permutation of digits), A107846 (number of duplicate digits of n). Also see A062813, which gives the largest number in each base containing all distinct digits. %K A109303 base,easy,nonn %O A109303 1,1 %A A109303 _Rick L. Shepherd_, Jun 24 2005