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.

A175277 Base-5 pandigital primes: primes having at least one of each digit 0,1,2,3,4, when written in base 5.

Original entry on oeis.org

3319, 3323, 3347, 3469, 3491, 3539, 3547, 3559, 3571, 3607, 3613, 3617, 3691, 3823, 3847, 3863, 4019, 4079, 4139, 4327, 4423, 4483, 4493, 4519, 4523, 4603, 4759, 4903, 4951, 5039, 5059, 5107, 5113, 5147, 5179, 5227, 5273, 5279, 5351, 5477, 5507, 5527
Offset: 1

Views

Author

M. F. Hasler, May 27 2010

Keywords

Comments

Terms in this sequence have at least 6 digits in base 5, i.e., are larger than 5^5, since sum(d_i 5^i) = sum(d_i) (mod 4), and 0+1+2+3+4 is divisible by 2. So the smallest ones should be of the form "10...." in base 5, where "...." is a permutation of "1234". By chance the identical permutation already yields a prime, i.e. a(1) = "101234" in base 5.

Crossrefs

Programs

  • Mathematica
    Select[Prime[Range[800]],Min[DigitCount[#,5]]>0&] (* Harvey P. Dale, Mar 10 2019 *)
  • PARI
    base(n,b=5,s=0)={local(a=[n%b]);while(09,s,48)+a[i])),a)}
    forprime(p=5^5,5^6,#Set(base(p,5))==5 & print1(p","))