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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A199348 Primes having only {3, 4, 8} as digits.

Original entry on oeis.org

3, 43, 83, 383, 433, 443, 883, 3343, 3433, 3833, 4483, 8443, 33343, 34483, 34843, 34883, 38333, 38833, 44383, 44483, 44843, 48383, 48883, 83383, 83443, 83833, 83843, 84443, 88843, 88883, 333383, 333433, 334333, 334843, 338383, 343333, 343433, 344483, 344843, 348433, 348443, 348833, 348883, 383483, 383833, 384343, 384383, 388483
Offset: 1

Views

Author

M. F. Hasler, Nov 05 2011

Keywords

Comments

All terms end in 3 and those > 3 never have the same number of 4's and 8's.

Crossrefs

Programs

  • Mathematica
    Table[Select[FromDigits/@Tuples[{3,4,8},n],PrimeQ],{n,6}]//Flatten (* Harvey P. Dale, Apr 09 2022 *)
  • PARI
    a(n, list=0, L=[3, 4, 8], reqpal=0)={my(t); for(d=1, 1e9, u=vector(d, i, 10^(d-i))~; forvec(v=vector(d, i, [1+(i==1&!L[1]), #L]), isprime(t=vector(d, i, L[v[i]])*u) || next; reqpal & !isprime(A004086(t)) & next; list & print1(t", "); n--||return(t)))}

A284069 Numbers whose smallest decimal digit is 8.

Original entry on oeis.org

8, 88, 89, 98, 888, 889, 898, 899, 988, 989, 998, 8888, 8889, 8898, 8899, 8988, 8989, 8998, 8999, 9888, 9889, 9898, 9899, 9988, 9989, 9998, 88888, 88889, 88898, 88899, 88988, 88989, 88998, 88999, 89888, 89889, 89898, 89899, 89988, 89989, 89998, 89999, 98888
Offset: 1

Views

Author

Jaroslav Krizek, Mar 24 2017

Keywords

Comments

Numbers n such that A054054(n) = 8.
Prime terms are in A020472. - Corrected by Robert Israel, Apr 05 2017

Crossrefs

Cf. Sequences of numbers whose smallest decimal digit is k (for k = 0..9): A011540 (k = 0), A284062 (k = 1), A284063 (k = 2), A284064 (k = 3), A284065 (k = 4), A284066 (k = 5), A284067 (k = 6), A284068 (k = 7), this sequence (k = 8), A002283 (k = 9).

Programs

  • Magma
    [n: n in [1..100000] | Minimum(Setseq(Set(Sort(&cat[Intseq(n)])))) eq 8]
    
  • Maple
    F:= proc(d) local r; # to get all terms with d digits
    r:= 8*(10^d-1)/9;
    op(sort(convert(map(t -> r + add(10^(j-1),j=t), combinat:-powerset(d) minus {{$1..d}}),list)))
    end proc:
    map(F, [$1..5]); # Robert Israel, Apr 05 2017
  • Mathematica
    Flatten@ Table[ Most[ FromDigits /@ Tuples[{8,9}, k]], {k,5}] (* Giovanni Resta, Mar 24 2017 *)
  • PARI
    isok(n) = vecmin(digits(n)) == 8; \\ Michel Marcus, Mar 25 2017
    
  • Python
    print([n for n in range(8, 10**6) if min(str(n))=='8']) # Indranil Ghosh, Apr 06 2017

Formula

From Robert Israel, Apr 05 2017: (Start)
a(2*j+2^(m+1)-m-3) = 10*a(j+2^m-m-1)+8 for j=1..2^m-1.
a(2*j+2^(m+1)-m-2) = 10*a(j+2^m-m-1)+9 for j=1..2^m-1.
a(2^(m+1)-m-2) = 10^m-2. (End)

A199326 Primes having only {0, 1, 6} as digits.

Original entry on oeis.org

11, 61, 101, 601, 661, 1061, 1601, 6011, 6101, 6661, 10061, 10111, 10601, 11161, 16001, 16061, 16111, 16661, 60101, 60161, 60601, 60611, 60661, 61001, 66161, 66601, 101111, 101161, 101611, 106661, 110161, 111611, 116101, 160001, 161611, 166601, 600011, 600101, 600601, 601061, 610661, 611011, 611101, 611111
Offset: 1

Views

Author

M. F. Hasler, Nov 05 2011

Keywords

Crossrefs

Programs

  • Mathematica
    Select[FromDigits/@Tuples[{0,1,6},6],PrimeQ] (* Harvey P. Dale, Dec 25 2018 *)
  • PARI
    {L=[0,1,6];for(d=1,6,u=vector(d,i,10^(d-i))~;forvec(v=vector(d,i,[1+(i==1 & !L[1]),#L]),ispseudoprime(t=vector(d,i,L[v[i]])*u)&print1(t",")))} /* see A199327 for a function a() */

A385783 Primes having only {1, 8, 9} as digits.

Original entry on oeis.org

11, 19, 89, 181, 191, 199, 811, 881, 911, 919, 991, 1181, 1811, 1889, 1999, 8111, 8191, 8819, 8999, 9181, 9199, 9811, 11119, 11981, 18119, 18181, 18191, 18199, 18899, 18911, 18919, 19181, 19819, 19889, 19891, 19919, 19991, 81119, 81181, 81199, 81899, 81919
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Crossrefs

Supersequence of A020456, A020457, A020472.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [1, 8, 9]];
    
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{1, 8, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [1, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("189"), 41))) # uses function/imports in A385776
    

A385790 Primes having only {2, 8, 9} as digits.

Original entry on oeis.org

2, 29, 89, 229, 829, 929, 2999, 8929, 8999, 9829, 9929, 22229, 28229, 28289, 29989, 82889, 88289, 89899, 89989, 92899, 98299, 98899, 98929, 98999, 99289, 99829, 99929, 99989, 222289, 228299, 228829, 228929, 228989, 282229, 282299, 282889, 288929, 288989, 289889
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Crossrefs

Supersequence of A020460, A020472.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [2, 8, 9]];
    
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{2, 8, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [2, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("289"), 41))) # uses function/imports in A385776
    

A385792 Primes having only {3, 8, 9} as digits.

Original entry on oeis.org

3, 83, 89, 383, 389, 839, 883, 983, 3389, 3833, 3889, 3989, 8389, 8839, 8893, 8933, 8999, 9833, 9839, 9883, 33889, 33893, 38333, 38393, 38833, 38839, 38933, 38993, 39383, 39839, 39883, 39983, 39989, 83339, 83383, 83389, 83399, 83833, 83933, 83939, 83983, 88339
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Crossrefs

Supersequence of A020464, A020472.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [3, 8, 9]];
    
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{3, 8, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [3, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("389"), 41))) # uses function/imports in A385776
    

A385798 Primes having only {5, 8, 9} as digits.

Original entry on oeis.org

5, 59, 89, 599, 859, 8599, 8999, 9859, 55589, 55889, 58889, 59999, 85889, 85999, 88589, 89599, 89899, 89959, 89989, 95959, 95989, 98899, 98999, 99559, 99859, 99989, 555589, 558599, 559859, 585889, 585899, 585989, 589859, 598999, 599899, 599959, 599999, 855889
Offset: 1

Views

Author

Jason Bard, Jul 14 2025

Keywords

Crossrefs

Supersequence of A020468, A020472.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [5, 8, 9]];
    
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{5, 8, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [5, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("589"), 41))) # uses function/imports in A385776
    

A385796 Primes having only {4, 8, 9} as digits.

Original entry on oeis.org

89, 449, 499, 4889, 4999, 8849, 8999, 9949, 44449, 48449, 48889, 48989, 49499, 49999, 84449, 84499, 88499, 89449, 89849, 89899, 89989, 94849, 94889, 94949, 94999, 98849, 98899, 98999, 99989, 444449, 448999, 449989, 484489, 484999, 489449, 489989, 494849, 494899
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Crossrefs

Subsequence of A030433.
Supersequence of A020466, A020472.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [4, 8, 9]];
    
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{4, 8, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [4, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("489"), 41))) # uses function/imports in A385776
    

A099651 For each of the C(10,2) = 45 pairs of decimal digits, record the smallest prime containing only these digits (if one exists); sort.

Original entry on oeis.org

13, 17, 19, 23, 29, 37, 41, 43, 47, 53, 59, 61, 67, 79, 83, 89, 101, 151, 181, 211, 227, 449, 557, 787
Offset: 1

Views

Author

Labos Elemer, Nov 11 2004

Keywords

Comments

The sequence consists of 24 terms, of which 16 cases < 100.
From 45 combinations of 10 decimal digits only 24 can be prime. All least cases are here.

Examples

			Primes with digits of 8 and 9 are in A020472:{89,8999,89899,89989..}. The smallest = 89 is here.
The 24 digit pairs sorted least to greatest that can be prime are {01, 12, 13, 14, 15, 16, 17, 18, 19, 23, 27, 29, 34, 35, 37, 38, 47, 49, 57, 59, 67, 78, 79, 89}. - _Michael De Vlieger_, Mar 02 2017
		

Crossrefs

Programs

  • Mathematica
    Sort@ Map[Module[{k = 1}, While[! SameQ[Union@ IntegerDigits@ Prime@ k, #], k++]; Prime@ k] &, Function[r, {{0, 1}}~Join~DeleteCases[Union@ Map[Sort, Tuples[Range@ 9, 2]], w_ /; Or[Times @@ Boole@ Map[EvenQ, w] > 0, SameQ @@ w, Times @@ Boole@ Map[Mod[#, 3] == 0 &, w] > 0, SubsetQ[r, w], w == {5, 6}]]]@ Select[Range[2, 9], PowerMod[10, #, #] == 0 &]] (* Michael De Vlieger, Mar 02 2017 *)

A385772 Primes having only {0, 8, 9} as digits.

Original entry on oeis.org

89, 809, 8009, 8089, 8999, 80809, 80909, 80989, 89009, 89809, 89899, 89909, 89989, 90089, 90989, 98009, 98809, 98899, 98909, 98999, 99089, 99809, 99989, 800089, 800909, 800999, 809909, 880909, 888809, 888989, 889909, 890809, 890999, 898889, 899009, 900089
Offset: 1

Views

Author

Jason Bard, Jul 09 2025

Keywords

Examples

			8999 is a term because it is prime and has only {0,8,9} as digits.
		

Crossrefs

Subsequence of A030433.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [0, 8, 9]];
    
  • Mathematica
    Select[FromDigits/@Tuples[{0,8,9},5],PrimeQ]
  • PARI
    primes_with(, 1, [0, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("089"), 41))) # uses function/imports in A385776
    
Previous Showing 21-30 of 41 results. Next