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.

A187372 Numbers k such that the decimal digits of 1/k contain every digit at least once.

Original entry on oeis.org

17, 19, 23, 29, 34, 38, 46, 47, 49, 51, 53, 57, 58, 59, 61, 68, 69, 71, 76, 83, 85, 87, 89, 92, 94, 95, 97, 98, 102, 103, 107, 109, 113, 114, 115, 116, 118, 119, 121, 122, 127, 129, 131, 133, 136, 138, 139, 141, 142, 145, 147, 149, 151, 152, 153, 157, 161, 163, 166, 167, 169, 170, 171, 173, 174, 177, 178, 179, 181, 183, 184, 188
Offset: 1

Views

Author

Michel Lagneau, Mar 09 2011

Keywords

Examples

			17 is in the sequence because 1/17 = .0588235294117647 0588235294117647 ...
contains every digit at least once ;
31 is not in the sequence because 1/31 = .032258064516129 032258064516129...
without the digit 7.
		

Crossrefs

Cf. A187614.

Programs

  • Maple
    with(numtheory):Digits:=200:B:={0, 1, 2, 3, 4, 5, 6, 7, 8, 9}: T:=array(1..250)
      : for p from 1 to 200 do:ind:=0:n:=floor(evalf(10^200/p)):l:=length(n):n0:=n:s:=0:for
      m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v : T[m]:=u:od: A:=convert(T,
      set):z:=nops(A):if A intersect B = B and ind=0 then ind:=1: printf(`%d, `, p):else
      fi:od:
  • Mathematica
    A2 := {}; Do[ If[Length[Union[IntegerDigits[Floor[10^200/n]]]] == 10, A2 =
      Join[A2, {n}]], {n, 1, 200}]; Print[A2]