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 1-10 of 10 results.

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

Links

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

A260268 Primes having only {1, 4, 5} as digits.

Original entry on oeis.org

5, 11, 41, 151, 541, 1151, 1451, 1511, 4111, 4441, 4451, 5441, 11411, 11551, 14411, 14551, 15451, 15511, 15541, 15551, 41141, 41411, 44111, 45541, 51151, 51511, 51551, 54151, 54541, 55411, 55441, 55511, 55541, 114451, 115151, 141511, 141551, 144451, 144511
Offset: 1

Views

Author

Vincenzo Librandi, Jul 23 2015

Keywords

Comments

A020452 and A020453 are subsequences.

Links

Crossrefs

Cf. similar sequences listed in A260266.
Cf. A020452, A020453.

Programs

  • Magma
    [p: p in PrimesUpTo(4*10^5) | Set(Intseq(p)) subset [1, 4, 5]];
  • Mathematica
    Select[Prime[Range[3 10^4]], Complement[IntegerDigits[#], {1, 4, 5}]=={} &]

A385779 Primes having only {1, 5, 6} as digits.

Original entry on oeis.org

5, 11, 61, 151, 661, 1151, 1511, 5651, 6151, 6551, 6661, 11161, 11551, 15161, 15511, 15551, 15661, 16111, 16561, 16651, 16661, 51151, 51511, 51551, 55511, 55661, 56611, 61151, 61511, 61561, 61651, 65111, 65551, 65651, 66161, 111611, 115151, 115561, 151561
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Links

Crossrefs

Supersequence of A020453, A020454.
Cf. A000040, A385776.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [1, 5, 6]];
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{1, 5, 6}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [1, 5, 6]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("156"), 41))) # uses function/imports in A385776

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

Links

Crossrefs

Subsequence of A030096. A004022, A020451, A020453, and A020462 are subsequences.
Cf. similar sequences listed in A260223.
Cf. A020451, A020453, A020462, A385776.

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

A385773 Primes having only {1, 2, 5} as digits.

Original entry on oeis.org

2, 5, 11, 151, 211, 251, 521, 1151, 1511, 2111, 2221, 2251, 2521, 2551, 5521, 11251, 11551, 12211, 12251, 12511, 15121, 15511, 15551, 21121, 21211, 21221, 21521, 22111, 22511, 25111, 25121, 51151, 51511, 51521, 51551, 52121, 52511, 55511, 111121, 111211
Offset: 1

Views

Author

Jason Bard, Jul 09 2025

Keywords

Links

Crossrefs

Supersequence of A024050, A020453.
Cf. A000040, A385776.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [1, 2, 5]];
  • Mathematica
    Flatten[Table[ Select[FromDigits /@ Tuples[{1, 2, 5}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [1, 2, 5]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("125"), 41))) # uses function/imports in A385776

A385780 Primes having only {1, 5, 8} as digits.

Original entry on oeis.org

5, 11, 151, 181, 811, 881, 1151, 1181, 1511, 1811, 5581, 5851, 5881, 8111, 8581, 11551, 15511, 15551, 15581, 15881, 18181, 51151, 51511, 51551, 51581, 55511, 58111, 58151, 58511, 81181, 81551, 88811, 111581, 115151, 115811, 155581, 155851, 158551, 158581
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Links

Crossrefs

Supersequence of A020453, A020456.
Cf. A000040, A385776.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [1, 5, 8]];
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{1, 5, 8}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [1, 5, 8]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("158"), 41))) # uses function/imports in A385776

A385781 Primes having only {1, 5, 9} as digits.

Original entry on oeis.org

5, 11, 19, 59, 151, 191, 199, 599, 911, 919, 991, 1151, 1511, 1559, 1951, 1999, 5119, 5519, 5591, 9151, 9199, 9511, 9551, 11119, 11159, 11519, 11551, 11959, 15199, 15511, 15551, 15559, 15919, 15959, 15991, 19559, 19919, 19991, 51151, 51199, 51511, 51551
Offset: 1

Views

Author

Jason Bard, Jul 13 2025

Keywords

Links

Crossrefs

Supersequence of A020453, A020457, A020468.
Cf. A000040, A385776.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [1, 5, 9]];
  • Mathematica
    Flatten[Table[Select[FromDigits /@ Tuples[{1, 5, 9}, n], PrimeQ], {n, 7}]]
  • PARI
    primes_with(, 1, [1, 5, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("159"), 41))) # uses function/imports in A385776

A036305 Composite numbers whose prime factors contain no digits other than 1 and 5.

Original entry on oeis.org

25, 55, 121, 125, 275, 605, 625, 755, 1331, 1375, 1661, 3025, 3125, 3775, 5755, 6655, 6875, 7555, 8305, 12661, 14641, 15125, 15625, 16621, 18271, 18875, 22801, 28775, 33275, 34375, 37775, 41525, 57755, 63305, 73205, 75625, 77555, 77755, 78125
Offset: 1

Views

Author

Patrick De Geest, Dec 15 1998

Keywords

Comments

All terms are a product of at least two terms of A020453. - David A. Corneth, Oct 09 2020

Links

Crossrefs

Cf. A003598, A020453, A036302-A036325.

Formula

Sum_{n>=1} 1/a(n) = Product_{p in A020453} (p/(p - 1)) - Sum_{p in A020453} 1/p - 1 = 0.0873463128... . - Amiram Eldar, May 18 2022

A036932 Smallest n-digit prime containing only digits 1 and 5, or 0 if no such prime exists.

Original entry on oeis.org

5, 11, 151, 1151, 11551, 115151, 1111151, 15511151, 111151511, 1111115111, 11111151551, 111111111511, 1111111155151, 11111111511151, 111111111155111, 1111111111155151, 11111111111115151, 111111111115151551
Offset: 1

Views

Author

Patrick De Geest, Jan 04 1999

Keywords

Links

Crossrefs

Cf. A020453, A036229, A036305.

Programs

  • Mathematica
    Table[SelectFirst[FromDigits/@Tuples[{1,5},n],PrimeQ],{n,20}] (* Harvey P. Dale, Aug 04 2019 *)

Extensions

Corrected by Harvey P. Dale, Mar 19 2013

A386331 Primes without {1, 5} as digits.

Original entry on oeis.org

2, 3, 7, 23, 29, 37, 43, 47, 67, 73, 79, 83, 89, 97, 223, 227, 229, 233, 239, 263, 269, 277, 283, 293, 307, 337, 347, 349, 367, 373, 379, 383, 389, 397, 409, 433, 439, 443, 449, 463, 467, 479, 487, 499, 607, 643, 647, 673, 677, 683, 709, 727, 733, 739, 743, 769
Offset: 1

Views

Author

Jason Bard, Jul 19 2025

Keywords

Links

Crossrefs

Intersection of A038603 and A038613.
Cf. A000040, A020453, A385776.

Programs

  • Magma
    [p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [0, 2, 3, 4, 6, 7, 8, 9]];
  • Maple
    f:= n-> (l-> add([0, $2..4, $6..9][l[j]+1]*10^(j-1), j=1..nops(l)))(convert(n, base, 8)):
select(isprime, [seq(f(i), i=0..600)])[];  # Alois P. Heinz, Jul 19 2025
  • Mathematica
    Select[Prime[Range[120]], DigitCount[#, 10, 1] == 0 && DigitCount[#, 10, 5] == 0 &]
  • PARI
    primes_with(, 1, [0, 2, 3, 4, 6, 7, 8, 9]) \\ uses function in A385776
  • Python
    print(list(islice(primes_with("02346789"), 41))) # uses function/imports in A385776
Showing 1-10 of 10 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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