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.

A187584 Least number divisible by at least n of its digits, different and > 1.

Original entry on oeis.org

2, 24, 248, 2364, 27384, 243768, 23469768, 1234759680
Offset: 1

Views

Author

Zak Seidov, Mar 11 2011

Keywords

Comments

a(1)=2=A185186(1), a(2)=24=A187516(1),
a(3)=248=A187398(1), a(4)=2364=A187238(1),
a(5)=27384=A187533(1), a(6)=243768=A187534(1),
a(7)=23469768=A187551(1), a(8)=1234759680=A187565(1).

Crossrefs

Programs

  • Mathematica
    divQ[m_, n_] := Length[(u = Union[Select[IntegerDigits[m], # > 1 &]])] >= n && Plus @@ (Boole@Divisible[m, u]) >= n; a[n_] := Module[{k = 1}, While[! divQ[k, n], k++]; k]; Array[a, 8] (* Amiram Eldar, Aug 30 2020 *)
  • Python
    def c(n): return len(set(d for d in str(n) if d>'1' and n%int(d)==0))
    def a(n):
      m = 2*10**(n-1)
      while c(m) < n: m += 1
      return m
    print([a(n) for n in range(1, 7)]) # Michael S. Branicky, Feb 24 2021

Extensions

a(8) corrected by David A. Corneth, Aug 30 2020