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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A020462 Primes that contain digits 3 and 5 only.

Original entry on oeis.org

3, 5, 53, 353, 3533, 5333, 33353, 33533, 35353, 35533, 53353, 55333, 333533, 353333, 533353, 535333, 3335533, 3353333, 3353533, 3355553, 3533533, 3553553, 3555353, 5333353, 5333533, 5353553, 5533553, 33335333, 33555553, 35535553, 35553533, 53355353, 53533553
Offset: 1

Views

Author

Keywords

Crossrefs

Subsequence of A030096.

Programs

  • Maple
    sort(convert(`union`(seq(select(isprime,map(t -> 3*(10^d-1)/9 + 2*add(10^(s-1),s=t),combinat:-powerset(d))),d=0..10)),list)); # Robert Israel, Jul 21 2015
  • Mathematica
    Flatten[Table[Select[FromDigits/@Tuples[{3,5},n],PrimeQ],{n,8}]] (* Vincenzo Librandi, Jul 27 2012 *)
  • Python
    from gmpy2 import is_prime, mpz
    from itertools import product
    A020462_list = [int(''.join(x)) for n in range(1,10) for x in product('35',repeat=n) if is_prime(mpz(''.join(x)))] # Chai Wah Wu, Jul 21 2015

A260831 Primes having only {5, 7, 9} as digits.

Original entry on oeis.org

5, 7, 59, 79, 97, 557, 577, 599, 757, 797, 977, 997, 5557, 5779, 7559, 7577, 7757, 7759, 55579, 55799, 55997, 57557, 57559, 57977, 59557, 59779, 59797, 59957, 59999, 75557, 75577, 75797, 75979, 75997, 77557, 77797, 77977, 77999, 79559, 79579, 79757, 79777
Offset: 1

Views

Author

Vincenzo Librandi, Aug 03 2015

Keywords

Comments

A020467, A020468 and A020471 are subsequences.
Subsequence of A030096.

Crossrefs

Cf. similar sequences listed in A260827.

Programs

  • Magma
    [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [5, 7, 9]];
  • Mathematica
    Select[Prime[Range[2 10^5]], Complement[IntegerDigits[#], {5, 7, 9}] == {} &]

A020467 Primes that contain digits 5 and 7 only.

Original entry on oeis.org

5, 7, 557, 577, 757, 5557, 7577, 7757, 57557, 75557, 75577, 77557, 555557, 575557, 575777, 577757, 757577, 775757, 775777, 5555777, 5557757, 5575777, 5577577, 5755577, 5775557, 5777557, 7575577, 7577777, 55555777, 55575757, 55755757, 55757777, 57557557
Offset: 1

Views

Author

Keywords

Crossrefs

Subsequence of A030096, A260827-A260831, and A284380.

Programs

  • Magma
    [p: p in PrimesUpTo(55755757 ) | Set(Intseq(p)) subset [5, 7]];// Vincenzo Librandi, Jul 27 2012
    
  • Mathematica
    Flatten[Table[Select[FromDigits/@Tuples[{5,7},n],PrimeQ],{n,8}]]
  • Python
    from sympy import isprime
    from sympy.utilities.iterables import multiset_permutations
    def aupton(terms):
      n, digits, alst = 0, 1, []
      while len(alst) < terms:
        mpstr = "".join(d*digits for d in "57")
        for mp in multiset_permutations(mpstr, digits):
          t = int("".join(mp))
          if isprime(t): alst.append(t)
          if len(alst) == terms: break
        else: digits += 1
      return alst
    print(aupton(33)) # Michael S. Branicky, May 07 2021

A260828 Primes having only {1, 5, 7} as digits.

Original entry on oeis.org

5, 7, 11, 17, 71, 151, 157, 557, 571, 577, 751, 757, 1117, 1151, 1171, 1511, 1571, 1777, 5171, 5557, 5711, 5717, 7151, 7177, 7517, 7577, 7717, 7757, 11117, 11171, 11177, 11551, 11717, 11777, 15511, 15551, 17117, 17551, 51151, 51157, 51511, 51517, 51551, 51577
Offset: 1

Views

Author

Vincenzo Librandi, Aug 02 2015

Keywords

Crossrefs

Subsequence of A030096. A020453, A020455 and A020467 are subsequences.
Cf. similar sequences listed in A260827.
Cf. A000040.

Programs

  • Magma
    [p: p in PrimesUpTo(2*10^5) | Set(Intseq(p)) subset [1,5,7]];
    
  • Mathematica
    Select[Prime[Range[2 10^4]], Complement[IntegerDigits[#], {1, 5, 7}] == {} &]
  • Python
    from sympy import isprime
    from sympy.utilities.iterables import multiset_permutations
    def aupton(terms):
      n, digits, alst = 0, 1, []
      while len(alst) < terms:
        mpstr = "".join(d*digits for d in "157")
        for mp in multiset_permutations(mpstr, digits):
          t = int("".join(mp))
          if isprime(t): alst.append(t)
          if len(alst) == terms: break
        else: digits += 1
      return alst
    print(aupton(44)) # Michael S. Branicky, May 07 2021

A051416 Primes whose digits are composite; primes having only {4, 6, 8, 9} as digits.

Original entry on oeis.org

89, 449, 499, 4649, 4889, 4969, 4999, 6449, 6469, 6689, 6869, 6899, 6949, 8669, 8689, 8699, 8849, 8969, 8999, 9649, 9689, 9949, 44449, 44699, 46489, 46499, 46649, 46889, 48449, 48649, 48869, 48889, 48989, 49499, 49669, 49999, 64489, 64499, 64849, 64969, 66449
Offset: 1

Views

Author

G. L. Honaker, Jr., Jan 17 2000

Keywords

Comments

Primes formed by using only digits 4, 6, 8, 9. Of course, all the terms of this sequence end with 9. - Bernard Schott, Jan 31 2019

Examples

			89 is the smallest composite-digit prime and also the only composite-digit prime whose digits are distinct. - _Bernard Schott_, Jan 31 2019
		

Crossrefs

Cf. A019546 (with prime digits), A030096 (with odd digits), A061246 (with square digits), A061371 (composite numbers with prime digits).
Subsequence of A061372 and of A152313.

Programs

  • Mathematica
    Select[Prime@Range[6500], Intersection[IntegerDigits[ # ], {0, 1, 2, 3, 5, 7}] == {} & ] (* Ray Chandler, Mar 04 2007 *)
    With[{c = {4, 6, 8, 9}}, Array[Select[Map[FromDigits@ Append[#, 9] &, Tuples[c, {#}]], PrimeQ] &, 4]] // Flatten (* Michael De Vlieger, Feb 02 2019 *)

Extensions

Extended by Ray Chandler, Mar 04 2007

A108386 Primes p such that p's set of distinct digits is {1,3,7,9}.

Original entry on oeis.org

1973, 3719, 3917, 7193, 9137, 9173, 9371, 13397, 13799, 13997, 17393, 17939, 19373, 19379, 19739, 19793, 19937, 19973, 31379, 31397, 31793, 31799, 31973, 33179, 33791, 37139, 37199, 37991, 39317, 39371, 39719, 39791, 39971, 71339, 71399
Offset: 1

Views

Author

Rick L. Shepherd, Jun 01 2005

Keywords

Comments

The digits in {1,3,7,9} are the possible ending digits of multidigit primes. [Corrected by Lekraj Beedassy, Apr 04 2009]
Subsequence of A091633. - Michel Marcus, Jun 08 2014

Crossrefs

Cf. A108382 ({1, 3, 7}), A108383 ({1, 3, 9}), A108384 ({1, 7, 9}), A108385 ({3, 7, 9}), A030096 (Primes whose digits are all odd).

A260379 Primes having only {1, 3, 7} as digits.

Original entry on oeis.org

3, 7, 11, 13, 17, 31, 37, 71, 73, 113, 131, 137, 173, 311, 313, 317, 331, 337, 373, 733, 773, 1117, 1171, 1373, 1733, 1777, 3137, 3313, 3331, 3371, 3373, 3733, 7177, 7331, 7333, 7717, 11113, 11117, 11131, 11171, 11173, 11177, 11311, 11317, 11717, 11731, 11777
Offset: 1

Views

Author

Vincenzo Librandi, Jul 24 2015

Keywords

Crossrefs

Subsequence of A030096 and A155055. A020451, A020455, and A020463 are subsequences.
Cf. similar sequences listed in A260378.

Programs

  • Magma
    [p: p in PrimesUpTo(2*10^4) | Set(Intseq(p)) subset [1, 3, 7]];
  • Mathematica
    Select[Prime[Range[2 10^3]], Complement[IntegerDigits[#], {1, 3, 7}]=={} &]

A260893 Primes having only {1, 7, 9} as digits.

Original entry on oeis.org

7, 11, 17, 19, 71, 79, 97, 179, 191, 197, 199, 719, 797, 911, 919, 971, 977, 991, 997, 1117, 1171, 1777, 1979, 1997, 1999, 7177, 7717, 7919, 9199, 9719, 9791, 11117, 11119, 11171, 11177, 11197, 11717, 11719, 11777, 11779, 11971, 17117, 17191, 17791, 17911
Offset: 1

Views

Author

Vincenzo Librandi, Aug 11 2015

Keywords

Comments

A020455, A020457 and A020471 are subsequences.
Subsequence of A030096.

Crossrefs

Cf. similar sequences listed in A260889.

Programs

  • Magma
    [p: p in PrimesUpTo(3*10^4) | Set(Intseq(p)) subset [1, 7, 9]];
  • Mathematica
    Select[Prime[Range[3 10^3]], Complement[IntegerDigits[#], {1, 7, 9}] == {}&]

A260224 Primes having only {1, 3, 5} as digits.

Original entry on oeis.org

3, 5, 11, 13, 31, 53, 113, 131, 151, 311, 313, 331, 353, 1151, 1153, 1511, 1531, 1553, 3313, 3331, 3511, 3533, 5113, 5153, 5333, 5351, 5531, 11113, 11131, 11311, 11351, 11353, 11551, 13151, 13313, 13331, 13513, 13553, 15131, 15313, 15331, 15511, 15551
Offset: 1

Views

Author

Vincenzo Librandi, Jul 21 2015

Keywords

Crossrefs

Subsequence of A030096. A004022, A020451, A020453, and A020462 are subsequences.
Cf. similar sequences listed in A260223.

Programs

  • Magma
    [p: p in PrimesUpTo(40000) | Set(Intseq(p)) subset [3, 5, 1]];
    
  • Mathematica
    Select[Prime[Range[3 10^3]], Complement[IntegerDigits[#], {3, 5, 1}]=={} &]
    Select[Flatten[Table[FromDigits/@Tuples[{1,3,5},n],{n,5}]],PrimeQ] (* Harvey P. Dale, Mar 03 2020 *)
  • Python
    from gmpy2 import is_prime, mpz
    from itertools import product
    A260224_list = [int(''.join(x)) for n in range(1,10) for x in product('135',repeat=n) if is_prime(mpz(''.join(x)))] # Chai Wah Wu, Jul 21 2015

A272381 Primes p == 1 (mod 3) for which A261029(10*p) = 2.

Original entry on oeis.org

7, 13, 19, 31, 37, 73
Offset: 1

Views

Author

Vladimir Shevelev, Apr 28 2016

Keywords

Comments

Peter J. C. Moses did not find any term > 73. The author proved that the sequence is full.

Crossrefs

Subsequence of A030096.
Cf. A261029.
Previous Showing 11-20 of 45 results. Next