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 1-4 of 4 results.

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

A337918 Rearrangement of natural numbers so that next n numbers contain n as substring.

Original entry on oeis.org

1, 2, 12, 3, 13, 23, 4, 14, 24, 34, 5, 15, 25, 35, 45, 6, 16, 26, 36, 46, 56, 7, 17, 27, 37, 47, 57, 67, 8, 18, 28, 38, 48, 58, 68, 78, 9, 19, 29, 39, 49, 59, 69, 79, 89, 10, 100, 101, 102, 103, 104, 105, 106, 107, 108, 11, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119
Offset: 1

Views

Author

Rémy Sigrist, Jan 29 2021

Keywords

Comments

This sequence combines features of A072484 and of A075383.
This sequence first differ from A075383 for n = 67: a(67) = 120 whereas A075383(67) = 12.
This sequence is a permutation of the natural numbers with inverse A337919.

Examples

			As a triangle, the first rows are:
     1: 1
     2: 2, 12
     3: 3, 13, 23
     4: 4, 14, 24, 34
     5: 5, 15, 25, 35, 45
     6: 6, 16, 26, 36, 46, 56
     7: 7, 17, 27, 37, 47, 57, 67
     8: 8, 18, 28, 38, 48, 58, 68, 78
     9: 9, 19, 29, 39, 49, 59, 69, 79, 89
    10: 10, 100, 101, 102, 103, 104, 105, 106, 107, 108
    11: 11, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119
    12: 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 212, 312
		

Crossrefs

Cf. A072484, A075383, A337919 (inverse).

Programs

  • Perl
    See Links section.

A072483 Triangle read by rows: The n-th row contains the smallest n increasing numbers larger than the last term of the previous row, which contain the string of digits of n.

Original entry on oeis.org

1, 2, 12, 13, 23, 30, 34, 40, 41, 42, 45, 50, 51, 52, 53, 56, 60, 61, 62, 63, 64, 67, 70, 71, 72, 73, 74, 75, 78, 80, 81, 82, 83, 84, 85, 86, 89, 90, 91, 92, 93, 94, 95, 96, 97, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117
Offset: 1

Views

Author

Amarnath Murthy, Jul 07 2002

Keywords

Examples

			The 6th row contains the 6 smallest numbers > 53 which contain the digit 6. The 10th row contains the 10 smallest numbers > 97 which contain the string "10".
The triangle starts
1
2 12
13 23 30
34 40 41 42
45 50 51 52 53
56 60 61 62 63 64
67 70 71 72 73 74 75
78 80 81 82 83 84 85 86
89 90 91 92 93 94 95 96 97
100 ...
		

Crossrefs

Cf. A072484.

Extensions

Edited by R. J. Mathar, Apr 18 2009
a(9)-a(10) corrected by Sean A. Irvine, Oct 04 2024

A072485 n-th number that includes the substring [n] in its decimal expansion.

Original entry on oeis.org

1, 12, 23, 34, 45, 56, 67, 78, 89, 108, 119, 129, 213, 314, 415, 516, 617, 718, 819, 920, 1021, 1220, 1223, 1240, 1251, 1262, 1273, 1284, 1295, 1306, 1317, 1328, 1433, 1349, 1435, 1536, 1637, 1738, 1839, 1940, 2041, 2142, 2243, 2441, 2445, 2460, 2471, 2482, 2493, 2504, 2515, 2526, 2537, 2548
Offset: 1

Views

Author

Amarnath Murthy, Jul 07 2002

Keywords

Crossrefs

Leading diagonal of triangle defined in A072484.

Programs

  • Maple
    N:= 100: count:= 0: R:= {$1..N}:
    V:= Vector(N):
    for n from 1 while count < N do
      Q:= map(proc(t) local i; seq(t mod 10^i,i=1..1+ilog10(t)) end proc,
        {seq(floor(n/10^i), i=0..ilog10(n))}) intersect R;
      for m in Q do
        V[m]:= V[m]+1;
        if V[m] = m then A[m]:= n; count:= count+1 fi
      od;
    od:
    seq(A[i],i=1..N); # Robert Israel, Sep 25 2019

Extensions

Corrected and extended by Robert Israel, Sep 25 2019
Showing 1-4 of 4 results.