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.

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A052383 Numbers without 1 as a digit.

Original entry on oeis.org

0, 2, 3, 4, 5, 6, 7, 8, 9, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 39, 40, 42, 43, 44, 45, 46, 47, 48, 49, 50, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62, 63, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 79, 80, 82, 83, 84, 85, 86, 87, 88, 89
Offset: 1

Views

Author

Henry Bottomley, Mar 13 2000

Keywords

Comments

For each k in {1, 2, ..., 29, 30, 32, 33, 34, 35, 37, 38, 39, 41, 42, 43} there exists at least an m such that m^k is 1-less. If m^k is 1-less then (10*m)^k, (100*m)^k, (1000*m)^k, ... are also 1-less. Therefore for each of these numbers k there exist infinitely many k-th powers in this sequence. - Mohammed Yaseen, Apr 17 2023

Crossrefs

Cf. A004176, A004720, A011531 (complement), A038603 (subset of primes), A082830 (Kempner series), A248518, A248519.
Cf. A052382 (without 0), A052404 (without 2), A052405 (without 3), A052406 (without 4), A052413 (without 5), A052414 (without 6), A052419 (without 7), A052421 (without 8), A007095 (without 9).

Programs

  • Haskell
    a052383 = f . subtract 1 where
       f 0 = 0
       f v = 10 * f w + if r > 0 then r + 1 else 0  where (w, r) = divMod v 9
    -- Reinhard Zumkeller, Oct 07 2014
    
  • Magma
    [ n: n in [0..89] | not 1 in Intseq(n) ];  // Bruno Berselli, May 28 2011
    
  • Maple
    M:= 3: # to get all terms with up to M digits
    B:= {$2..9}: A:= B union {0}:
    for m from 1 to M do
    B:= map(b -> seq(10*b+j,j={0,$2..9}), B);
    A:= A union B;
    od:
    sort(convert(A,list)); # Robert Israel, Jan 11 2016
    # second program:
    A052383 := proc(n)
          option remember;
          if n = 1 then
            0;
        else
            for a from procname(n-1)+1 do
                if nops(convert(convert(a,base,10),set) intersect {1}) = 0 then
                    return a;
                end if;
            end do:
        end if;
    end proc: # R. J. Mathar, Jul 31 2016
    # third Maple program:
    a:= proc(n) local l, m; l, m:= 0, n-1;
          while m>0 do l:= (d->
            `if`(d=0, 0, d+1))(irem(m, 9, 'm')), l
          od; parse(cat(l))/10
        end:
    seq(a(n), n=1..100);  # Alois P. Heinz, Aug 01 2016
  • Mathematica
    ban1Q[n_] := FreeQ[IntegerDigits[n], 1] == True; Select[Range[0, 89], ban1Q[#] &] (* Jayanta Basu, May 17 2013 *)
    Select[Range[0, 99], DigitCount[#, 10, 1] == 0 &] (* Alonso del Arte, Jan 12 2020 *)
  • PARI
    a(n)=my(v=digits(n,9));for(i=1,#v,if(v[i],v[i]++));subst(Pol(v),'x,10) \\ Charles R Greathouse IV, Oct 04 2012
    
  • PARI
    apply( {A052383(n)=fromdigits(apply(d->d+!!d, digits(n-1, 9)))}, [1..99]) \\ Defines the function and computes it for indices 1..99 (check & illustration)
    select( {is_A052383(n)=!setsearch(Set(digits(n)), 1)}, [0..99]) \\ Define the characteristic function is_A; as illustration, select the terms in [0..99]
    next_A052383(n, d=digits(n+=1))={for(i=1, #d, d[i]==1&& return((1+n\d=10^(#d-i))*d)); n} \\ Successor function: efficiently skip to the next a(k) > n. Used in A038603.  - M. F. Hasler, Jan 11 2020
    
  • Python
    from itertools import count, islice, product
    def A052383(): # generator of terms
        yield 0
        for digits in count(1):
            for f in "23456789":
                for r in product("023456789", repeat=digits-1):
                    yield int(f+"".join(r))
    print(list(islice(A052383(), 72))) # Michael S. Branicky, Oct 15 2023
    
  • Python
    from gmpy2 import digits
    def A052383(n): return int(''.join(str(int(d)+(d!='0')) for d in digits(n-1,9))) # Chai Wah Wu, Jun 28 2025
  • Scala
    (0 to 99).filter(.toString.indexOf('1') == -1) // _Alonso del Arte, Jan 12 2020
    
  • sh
    seq 0 1000 | grep -v 1; # Joerg Arndt, May 29 2011
    

Formula

a(1) = 1, a(n + 1) = f(a(n) + 1, a(n) + 1) where f(x, y) = if x < 10 and x <> 1 then y else if x mod 10 = 1 then f(y + 1, y + 1) else f(floor(x/10), y). - Reinhard Zumkeller, Mar 02 2008
a(n) is the replacement of all nonzero digits d by d + 1 in the base-9 representation of n - 1. - Reinhard Zumkeller, Oct 07 2014
Sum_{k>1} 1/a(k) = A082830 = 16.176969... (Kempner series). - Bernard Schott, Jan 12 2020

Extensions

Offset changed by Reinhard Zumkeller, Oct 07 2014

A011533 Numbers that contain a 3.

Original entry on oeis.org

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
Offset: 1

Views

Author

Keywords

Crossrefs

Complement: A052405.
Cf. A016189.
Numbers that contain a digit k: A011531 (k=1), A011532 (k=2), A011534 (k=4), A011535 (k=5), A011536 (k=6), A011537 (k=7), A011538 (k=8), A011539 (k=9), A011540 (k=0).

Programs

  • GAP
    Filtered([1..260],n->3 in ListOfDigits(n)); # Muniru A Asiru, Feb 23 2019
  • 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
    
  • 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 *)
  • PARI
    isok(n)=my(d=digits(n)); for (k=1, #d, if (d[k] == 3, return (1))); \\ Michel Marcus, Jan 11 2016
    

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

A011534 Numbers that contain a 4.

Original entry on oeis.org

4, 14, 24, 34, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 54, 64, 74, 84, 94, 104, 114, 124, 134, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 154, 164, 174, 184, 194, 204, 214, 224, 234, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 254
Offset: 1

Views

Author

Keywords

Crossrefs

Numbers that contain a digit k: A011531 (k=1), A011532 (k=2), A011533 (k=3), A011535 (k=5), A011536 (k=6), A011537 (k=7), A011538 (k=8), A011539 (k=9), A011540 (k=0).

Programs

Formula

a(n) ~ n. - Charles R Greathouse IV, Feb 12 2017

A131835 Numbers starting with 1.

Original entry on oeis.org

1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142
Offset: 1

Views

Author

Andrew Good (yipes_stripes(AT)yahoo.com), Jul 20 2007

Keywords

Comments

The lower and upper asymptotic densities of this sequence are 1/9 and 5/9, respectively. - Amiram Eldar, Feb 27 2021

Crossrefs

Subsequence of A011531.
Disjoint union of A045707 and A206286.
Cf. A000030, A000027, A002275, A262390 (permutation).

Programs

  • Haskell
    a131835 n = a131835_list !! (n-1)
    a131835_list = concat $
                   iterate (concatMap (\x -> map (+ 10 * x) [0..9])) [1]
    -- Reinhard Zumkeller, Jul 16 2014
    
  • Maple
    isA131835 := proc(n) if op(-1,convert(n,base,10)) = 1 then true; else false ; fi ; end: for n from 1 to 300 do if isA131835(n) then printf("%d, ",n) ; fi ; od : # R. J. Mathar, Jul 24 2007
  • Mathematica
    Select[Range[150], IntegerDigits[#][[1]] == 1 &] (* Amiram Eldar, Feb 27 2021 *)
  • PARI
    a(n, {base=10}) = my (o=1); while (n>o, n-=o; o*=base); return (o+n-1) \\ Rémy Sigrist, Jun 23 2017
    
  • PARI
    a(n) = n--; s = #digits(9*n+1); n + 8 * (10^(s-1))/9 + 1/9 \\ David A. Corneth, Jun 23 2017
    
  • PARI
    nxt(n) = my(d = digits(n+1)); if(d[1]==1, n+1, 10^#d) \\ David A. Corneth, Jun 23 2017
    
  • Python
    def A131835(n): return n+(10**(len(str(9*n-8))-1)<<3)//9 # Chai Wah Wu, Dec 07 2024

Formula

A000030(a(n)) = 1. - Reinhard Zumkeller, Jul 16 2014
a(A002275(n)+1) = 10^n for any n >= 0. - Rémy Sigrist, Jun 23 2017
a(n) = n + (8*10^floor(log_10(9*n-8))-8)/9. - Alan Michael Gómez Calderón, May 16 2023

Extensions

More terms from R. J. Mathar, Jul 24 2007

A082830 Decimal expansion of Kempner series Sum_{k>=1, k has no digit 1 in base 10} 1/k.

Original entry on oeis.org

1, 6, 1, 7, 6, 9, 6, 9, 5, 2, 8, 1, 2, 3, 4, 4, 4, 2, 6, 6, 5, 7, 9, 6, 0, 3, 8, 8, 0, 3, 6, 4, 0, 0, 9, 3, 0, 5, 5, 6, 7, 2, 1, 9, 7, 9, 0, 7, 6, 3, 1, 3, 3, 8, 6, 4, 5, 1, 6, 9, 0, 6, 4, 9, 0, 8, 3, 6, 3, 6, 2, 9, 8, 8, 9, 9, 9, 9, 9, 6, 4, 5, 6, 3, 8, 8, 8, 6, 2, 1, 4, 6, 2, 6, 6, 8, 5, 0, 2, 8, 6, 2, 9, 7, 7
Offset: 2

Views

Author

Robert G. Wilson v, Apr 14 2003

Keywords

Comments

Such sums are called Kempner series, see A082839 (the analog for digit 0) for more information. - M. F. Hasler, Jan 13 2020

Examples

			16.17696952812344426657...
		

References

  • Julian Havil, Gamma, Exploring Euler's Constant, Princeton University Press, Princeton and Oxford, 2003, page 34.

Crossrefs

Cf. A002387, A024101, A052383 (numbers without '1'), A011531 (numbers with '1').
Cf. A082831, A082832, A082833, A082834, A082835, A082836, A082837, A082838, A082839 (analog for digits 2, ..., 9 and 0).

Programs

  • Mathematica
    (* see the Mmca in Wolfram Library Archive. - Robert G. Wilson v, Jun 01 2009 *)

Formula

Equals Sum_{k in A052383\{0}} 1/k, where A052383 = numbers with no digit 1. Those which have a digit 1 (A011531) are omitted in the harmonic sum, and they have asymptotic density 1: almost all terms are omitted from the sum. - M. F. Hasler, Jan 15 2020

Extensions

More terms from Robert G. Wilson v, Jun 01 2009

A256786 Numbers which are divisible by prime(d) for all digits d in their decimal representation.

Original entry on oeis.org

12, 14, 42, 55, 154, 222, 228, 714, 1122, 1196, 1212, 1414, 2112, 2142, 2262, 3355, 4144, 4242, 5335, 5544, 5555, 6162, 9499, 11112, 11144, 11214, 11424, 11466, 11622, 11818, 11914, 12222, 12882, 14112, 15554, 16666, 21216, 21222, 21252, 21888, 22122, 22212
Offset: 1

Views

Author

Keywords

Comments

All terms are zerofree, cf. A052382;
there is no term containing digits 1 and 3 simultaneously;
a(n) contains at least one digit 1 iff a(n) is even, cf. A011531, A005843;
a(n) contains at least one digit 2 iff a(n) mod 3 = 0, cf. A011532, A008585;
a(n) contains at least one digit 3 iff a(n) mod 10 = 5, cf. A011533, A017329;
A020639(a(n)) <= 23.
The equivalent in base 2 is the empty sequence, in base 3 it is A191681\{0}; see A256874-A256879 for the base 4 - base 9 variant, and A256870 for a variant where digits 0 are allowed but divisibility by prime(d+1) is required instead. - M. F. Hasler, Apr 11 2015

Examples

			Smallest terms containing the nonzero decimal digits:
.  d | prime(d) |  n | a(n)
. ---+----------+--------------------------
.  1 |       2  |  1 |   12 = 2^2 * 3
.  2 |       3  |  1 |   12 = 2^2 * 3
.  3 |       5  | 16 | 3355 = 5 * 11 * 61
.  4 |       7  |  2 |   14 = 2 * 7
.  5 |      11  |  4 |   55 = 5 * 11
.  6 |      13  | 10 | 1196 = 2^2 * 13 * 23
.  7 |      17  |  8 |  714 = 2 * 3 * 7 * 17
.  8 |      19  |  7 |  228 = 2^2 * 3 * 19
.  9 |      23  | 10 | 1196 = 2^2 * 13 * 23 .
		

Crossrefs

Programs

  • Haskell
    a256786 n = a256786_list !! (n-1)
    a256786_list = filter f a052382_list where
       f x = g x where
         g z = z == 0 || x `mod` a000040 d == 0 && g z'
               where (z', d) = divMod z 10
    
  • Mathematica
    Select[Range@22222,FreeQ[IntegerDigits[#],0]&&Total[Mod[#,Prime[IntegerDigits[#]]]]==0&] (* Ivan N. Ianakiev, Apr 11 2015 *)
  • PARI
    is_A256786(n)=!for(i=1,#d=Set(digits(n)),(!d[i]||n%prime(d[i]))&&return) \\ M. F. Hasler, Apr 11 2015
    
  • Python
    primes = [1, 2, 3, 5, 7, 11, 13, 17, 19, 23]
    def ok(n):
        s = str(n)
        return "0" not in s and all(n%primes[int(d)] == 0 for d in s)
    print([k for k in range(22213) if ok(k)]) # Michael S. Branicky, Dec 14 2021

A293869 Square array whose n-th row lists all numbers having n as a substring, n >= 1; read by falling antidiagonals.

Original entry on oeis.org

1, 10, 2, 11, 12, 3, 12, 20, 13, 4, 13, 21, 23, 14, 5, 14, 22, 30, 24, 15, 6, 15, 23, 31, 34, 25, 16, 7, 16, 24, 32, 40, 35, 26, 17, 8, 17, 25, 33, 41, 45, 36, 27, 18, 9, 18, 26, 34, 42, 50, 46, 37, 28, 19, 10, 19, 27, 35, 43, 51, 56, 47, 38, 29, 100, 11
Offset: 1

Views

Author

M. F. Hasler, Oct 18 2017

Keywords

Examples

			The array starts:
   [ 1  10  11  12  13  14  15  16  17  18  19  21  31 ...] = A011531
   [ 2  12  20  21  22  23  24  25  26  27  28  29  32 ...] = A011532
   [ 3  13  23  30  31  32  33  34  35  36  37  38  39 ...] = A011533
   [ 4  14  24  34  40  41  42  43  44  45  46  47  48 ...] = A011534
   [ 5  15  25  35  45  50  51  52  53  54  55  56  57 ...] = A011535
   [ 6  16  26  36  46  56  60  61  62  63  64  65  66 ...] = A011536
   [ 7  17  27  37  47  57  67  70  71  72  73  74  75 ...] = A011537
   [ 8  18  28  38  48  58  68  78  80  81  82  83  84 ...] = A011538
   [ 9  19  29  39  49  59  69  79  89  90  91  92  93 ...] = A011539
   [10 100 101 102 103 104 105 106 107 108 109 110 210 ...] = A293870
   [11 110 111 112 113 114 115 116 117 118 119 211 311 ...] = A293871
   [12 112 120 121 122 123 124 125 126 127 128 129 212 ...] = A293872
   [   ...             ...             ...             ...]
		

Crossrefs

Cf. A072484, A292690 (variant starting with row 0).
Cf. A292451, A292731 (both partially coincide with row 11, but no inclusion relation holds).

Programs

  • Mathematica
    Block[{d = 15, q, a, s}, a = Table[q = n-1; s = IntegerString[n]; Table[While[StringFreeQ[IntegerString[++q], s]]; q, d-n+1], {n, d}]; Table[a[[n, k-n+1]], {k, d}, {n, k}]] (* Paolo Xausa, Mar 01 2024 *)
  • PARI
    has=(n,p,m=10^#Str(p))->until(p>n\=10,n%m==p&&return(1))
    Mat(vectorv(12,n,a=[];for(k=n,oo,has(k,n)||next;a=concat(a,k);#a>12&&break);a))
    
  • Perl
    See Links section.

Formula

T(n, k) = A072484(n, k) for any n > 0 and k = 1..n. - Rémy Sigrist, Jan 29 2021

A043493 Numbers that contain a single 1.

Original entry on oeis.org

1, 10, 12, 13, 14, 15, 16, 17, 18, 19, 21, 31, 41, 51, 61, 71, 81, 91, 100, 102, 103, 104, 105, 106, 107, 108, 109, 120, 122, 123, 124, 125, 126, 127, 128, 129, 130, 132, 133, 134, 135, 136, 137, 138, 139, 140, 142, 143, 144, 145
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

Formula

a(n) >> n^k where k = log(10)/log(9) = 1.04795.... - Charles R Greathouse IV, Jan 21 2025

A292690 Square array whose n-th row lists all numbers having n as a substring, read by falling antidiagonals, n >= 0.

Original entry on oeis.org

0, 10, 1, 20, 10, 2, 30, 11, 12, 3, 40, 12, 20, 13, 4, 50, 13, 21, 23, 14, 5, 60, 14, 22, 30, 24, 15, 6, 70, 15, 23, 31, 34, 25, 16, 7, 80, 16, 24, 32, 40, 35, 26, 17, 8, 90, 17, 25, 33, 41, 45, 36, 27, 18, 9, 100, 18, 26, 34, 42, 50, 46, 37, 28, 19, 10
Offset: 0

Views

Author

M. F. Hasler, Oct 18 2017

Keywords

Comments

This array starts with row 0, see A293869 for the variant which starts with row 1.

Examples

			The array starts:
   [ 0  10  20  30  40  50  60  70  80  90 100 101 102 ...] = A011540
   [ 1  10  11  12  13  14  15  16  17  18  19  21  31 ...] = A011531
   [ 2  12  20  21  22  23  24  25  26  27  28  29  32 ...] = A011532
   [ 3  13  23  30  31  32  33  34  35  36  37  38  39 ...] = A011533
   [ 4  14  24  34  40  41  42  43  44  45  46  47  48 ...] = A011534
   [ 5  15  25  35  45  50  51  52  53  54  55  56  57 ...] = A011535
   [ 6  16  26  36  46  56  60  61  62  63  64  65  66 ...] = A011536
   [ 7  17  27  37  47  57  67  70  71  72  73  74  75 ...] = A011537
   [ 8  18  28  38  48  58  68  78  80  81  82  83  84 ...] = A011538
   [ 9  19  29  39  49  59  69  79  89  90  91  92  93 ...] = A011539
   [10 100 101 102 103 104 105 106 107 108 109 110 210 ...] = A293870
   [11 110 111 112 113 114 115 116 117 118 119 211 311 ...] = A293871
   [12 112 120 121 122 123 124 125 126 127 128 129 212 ...] = A293872
   [   ...             ...             ...             ...]
		

Crossrefs

Programs

  • Mathematica
    Block[{d = 15, q, a, s}, a = Table[q = n-1; s = IntegerString[n]; Table[While[StringFreeQ[IntegerString[++q], s]]; q, d-n], {n, 0, d-1}]; Table[a[[n+1, k-n]], {k, d}, {n, 0, k-1}]] (* Paolo Xausa, Mar 01 2024 *)
  • PARI
    has(n,p,m=10^#Str(p))=until(p+!p>n\=10,n%m==p&&return(1))
    Mat(vectorv(12,n,a=[];for(k=n--,oo,has(k,n)||next;a=concat(a,k);#a>12&&break);a))
    for(i=1,11,for(j=1,i,print1(%[j,i-j+1]","))) \\ Read by antidiagonals

A293871 Numbers having 11 as substring of their digits.

Original entry on oeis.org

11, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 211, 311, 411, 511, 611, 711, 811, 911, 1011, 1100, 1101, 1102, 1103, 1104, 1105, 1106, 1107, 1108, 1109, 1110, 1111, 1112, 1113, 1114, 1115, 1116, 1117, 1118, 1119, 1120, 1121, 1122, 1123, 1124, 1125, 1126, 1127, 1128, 1129, 1130, 1131
Offset: 1

Views

Author

M. F. Hasler, Oct 18 2017

Keywords

Crossrefs

Row 11 of A292690 and A293869.
Cf. A292451, A292731 (both partially coincide with this sequence, but no inclusion relation holds).
Cf. A011540, A011531, A011532, A011533, A011534, A011535, A011536, A011537, A011538, A011539: analog for substrings '0' through '9'.
Cf. A293870, A293872, A293873, A293874, A293875, A293876, A293877, A293878, A293879, A293880: same for substrings '10' - '20'.
Cf. A121031: subsequence of terms divisible by 11.
Numbers divisible by k and having k as a substring: A121022 (2), A121023 (3), A121024 (4), A121025 (5), A121026 (6), A121027 (7), A121028 (8), A121029 (9), A121030 (10), A121031 (11), A121032 (12), A121033 (13), A121034 (14), A121035 (15), A121036 (16), A121037 (17), A121038 (18), A121039 (19), A121040 (20).
Cf. A121041.

Programs

  • Mathematica
    Select[Range[2000], StringContainsQ[IntegerString[#], "11"] &] (* Paolo Xausa, Feb 25 2024 *)
  • PARI
    is_A293871 = has(n,p=11,m=10^#Str(p))=until(p>n\=10,n%m==p&&return(1))

Formula

a(n) ~ n. - Charles R Greathouse IV, Nov 02 2022
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