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.

A199341 Primes having only {1, 3, 4} as digits.

Original entry on oeis.org

3, 11, 13, 31, 41, 43, 113, 131, 311, 313, 331, 431, 433, 443, 1433, 3313, 3331, 3343, 3413, 3433, 4111, 4133, 4441, 11113, 11131, 11311, 11411, 11443, 13313, 13331, 13411, 13441, 14143, 14341, 14411, 14431, 31333, 33113, 33311, 33331, 33343, 33413, 34141, 34313
Offset: 1

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Author

M. F. Hasler, Nov 05 2011

Keywords

Comments

A020451, A020452 and A020461 are subsequences. - Vincenzo Librandi, Jul 26 2015

Crossrefs

Cf. similar sequences listed in A199340.

Programs

  • Magma
    [p: p in PrimesUpTo(10^5) | Set(Intseq(p)) subset [3, 4, 1]]; // Vincenzo Librandi, Jul 26 2015
  • Maple
    Dmax:= 5: # to get all terms < 10^Dmax
    Cd:= {1,3,4}:
    C:= Cd:
    for d from 2 to Dmax do
      Cd:= map(t -> (10*t+1,10*t+3,10*t+4),Cd);
      C:= C union Cd;
    od:
    sort(convert(select(isprime,C),list)); # Robert Israel, Jul 26 2015
  • Mathematica
    Select[Prime[Range[4 10^3]], Complement[IntegerDigits[#], {3, 4, 1}]=={} &] (* Vincenzo Librandi, Jul 26 2015 *)
  • PARI
    a(n, list=0, L=[1, 3, 4], 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)))}