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.

A071519 Numbers whose square is a zeroless pandigital number (i.e., use the digits 1 through 9 once).

Original entry on oeis.org

11826, 12363, 12543, 14676, 15681, 15963, 18072, 19023, 19377, 19569, 19629, 20316, 22887, 23019, 23178, 23439, 24237, 24276, 24441, 24807, 25059, 25572, 25941, 26409, 26733, 27129, 27273, 29034, 29106, 30384
Offset: 1

Views

Author

Lekraj Beedassy, Jun 20 2002

Keywords

Crossrefs

A subset of A054037.

Programs

  • Maple
    lim:=floor(sqrt(987654321)): for n from floor(sqrt(123456789)) to lim do d:=[op(convert(n^2, base, 10))]: pandig:=true: for k from 1 to 9 do if(numboccur(k, d)<>1)then pandig:=false: break: fi: od: if(pandig)then printf("%d, ", n): fi: od: # Nathaniel Johnston, Jun 22 2011
  • Mathematica
    Sqrt[#]&/@Select[FromDigits/@Permutations[Range[9]],IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Sep 23 2011 *)
    Select[Range[11112, 31427,3], DigitCount[#^2] == {1,1,1,1,1,1,1,1,1,0} &]  (* Zak Seidov, Jan 11 2012 *)
  • PARI
    A071519 = select( {is_A071519(n,L=[1..9])=vecsort(digits(n^2))==L}, [1e5\9..1e5\3]) \\ M. F. Hasler, Jun 28 2023

Formula

a(n) = sqrt(A036744(n)). - Zak Seidov, Jan 11 2012