cp's OEIS Frontend

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.

Showing 1-7 of 7 results.

A109303 Numbers k with at least one duplicate base-10 digit (A107846(k) > 0).

Original entry on oeis.org

11, 22, 33, 44, 55, 66, 77, 88, 99, 100, 101, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 131, 133, 141, 144, 151, 155, 161, 166, 171, 177, 181, 188, 191, 199, 200, 202, 211, 212, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 232, 233, 242
Offset: 1

Views

Author

Rick L. Shepherd, Jun 24 2005

Keywords

Comments

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.
A178788(a(n)) = 0; A178787(a(n)) = A178787(a(n)-1); A043537(a(n)) < A109303(a(n)). - Reinhard Zumkeller, Jun 30 2010
A227362(a(n)) < a(n). - Reinhard Zumkeller, Jul 09 2013

Crossrefs

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.

Programs

  • Haskell
    a109303 n = a109303_list !! (n-1)
    a109303_list = filter ((> 0) . a107846) [0..]
    -- Reinhard Zumkeller, Jul 09 2013
    
  • Mathematica
    Select[Range[300], Max[DigitCount[#]] > 1 &] (* Harvey P. Dale, Jan 14 2011 *)
  • Python
    def ok(n): s = str(n); return len(set(s)) < len(s)
    print([k for k in range(243) if ok(k)]) # Michael S. Branicky, Nov 22 2021

A084050 Numbers n such that at least one permutation of the digits of n yields a palindrome.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 20, 22, 30, 33, 40, 44, 50, 55, 60, 66, 70, 77, 80, 88, 90, 99, 100, 101, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 131, 133, 141, 144, 151, 155, 161, 166, 171, 177, 181, 188, 191, 199, 200, 202, 211, 212, 220, 221
Offset: 1

Views

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 26 2003

Keywords

Comments

Union of A037124 and numbers with at most one decimal digit occurring an odd number of times. a(281)=1001 is the first term greater than 90 not also a term of A044959. The terms greater than 90 are a subsequence of A109303. - Rick L. Shepherd, Jun 24 2005

Crossrefs

Cf. A037124 (numbers with only one nonzero digit), A109303 (numbers with at least one duplicate digit).

Extensions

Corrected by Rick L. Shepherd, Jun 24 2005

A353181 Numbers in which more than half of the digits are the same.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 100, 101, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 122, 131, 133, 141, 144, 151, 155, 161, 166, 171, 177, 181, 188, 191, 199, 200, 202, 211, 212, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 232
Offset: 1

Views

Author

Zhining Yang, Apr 29 2022

Keywords

Comments

Same as A044959 for terms <= 1000, and then differing at A044959(272) = 1001 which is not a term here (the next instead a(272) = 1011).

Examples

			1211 is a term: it has 4 digits, 3 of which are 1's, and 3/4 > 1/2.
1212 is not a term: it has 4 digits, no one of which appears more than twice.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[300], Max[DigitCount[#]] > IntegerLength[#]/2 &]
  • Python
    def ok(k):
        t=str(k)
        return(max(t.count(str(i)) for i in range(10))>(len(t)//2))
    print([n for n in range(1, 201) if ok(n)])

A048321 Reading a(n) expansion from left to right, run lengths strictly decrease.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 330, 331, 332, 333, 334, 335, 336, 337, 338, 339, 440, 441, 442, 443, 444, 445, 446, 447, 448
Offset: 1

Views

Author

Patrick De Geest, Feb 15 1999

Keywords

Crossrefs

Programs

  • Haskell
    import Data.List (group)
    a048321 n = a048321_list !! (n-1)
    a048321_list = filter f [0..] where
       f x = all (< 0) $ zipWith (-) (tail zs) zs
             where zs =  map length $ group $ show x
    -- Reinhard Zumkeller, May 01 2015

A084051 Smallest palindrome corresponding to A084050(n).

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 11, 2, 22, 3, 33, 4, 44, 5, 55, 6, 66, 7, 77, 8, 88, 9, 99, 1, 101, 11, 111, 121, 131, 141, 151, 161, 171, 181, 191, 121, 212, 131, 313, 141, 414, 151, 515, 161, 616, 171, 717, 181, 818, 191, 919, 2, 202, 121, 212, 22, 212, 222, 232, 242, 252
Offset: 0

Views

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 26 2003

Keywords

Crossrefs

Extensions

Corrected by Rick L. Shepherd, Jun 24 2005

A121977 Numbers with a distinct frequency for each decimal digit.

Original entry on oeis.org

100000000011111112222222333333444445555666778, 100000000011111112222222333333444445555666779, 100000000011111112222222333333444445555666787, 100000000011111112222222333333444445555666788, 100000000011111112222222333333444445555666797, 100000000011111112222222333333444445555666799, 100000000011111112222222333333444445555666877, 100000000011111112222222333333444445555666878
Offset: 1

Views

Author

Keywords

Examples

			100000000011111112222222333333444445555666778 has 9 0's, 8 1's, 7 2's, 6 3's, 5 4's, 4 5's, 3 6's, 2 7's, 1 8 and 0 9's. 121 is not in the sequence because there are eight digits it has zero of.
		

Crossrefs

Subsequence of A179239.

A048307 Numbers whose decimal expansions, read from left to right, have run lengths that strictly increase.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99, 100, 111, 122, 133, 144, 155, 166, 177, 188, 199, 200, 211, 222, 233, 244, 255, 266, 277, 288, 299, 300, 311, 322, 333, 344, 355, 366, 377, 388, 399, 400, 411, 422, 433, 444, 455, 466, 477, 488
Offset: 0

Views

Author

Patrick De Geest, Feb 15 1999

Keywords

Crossrefs

Showing 1-7 of 7 results.