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.

A096093 Numbers, not divisible by 10, whose digits can be permuted to get a proper divisor.

Original entry on oeis.org

105, 108, 405, 702, 703, 1001, 1005, 1008, 1053, 2002, 2016, 2025, 2079, 2106, 3003, 3024, 3042, 3045, 3105, 3402, 4004, 4005, 5005, 5049, 6006, 6031, 6045, 6048, 6072, 6075, 6084, 6105, 6804, 7007, 7011, 7128, 7425, 8008, 8019, 8092, 8316, 8712, 9009
Offset: 1

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Author

Amarnath Murthy, Jun 22 2004

Keywords

Examples

			105 is a term as 015 is a proper divisor of 105.
2178 is a proper divisor of 8712 and 8712/2178=4.
1089 is a proper divisor of 9801 and 9801/1089=9.
		

Crossrefs

Cf. A096092.

Programs

  • Maple
    filter:= proc(n) local L,nL,P;
      L:= convert(n,base,10);
      nL:= nops(L);
      P:= subs(L=NULL, combinat:-permute(L));
      ormap(p -> n mod add(p[i]*10^(i-1),i=1..nL) = 0, P)
    end proc:
    select(filter, [seq(seq(10*i+j,j=1..9),i=1..10000)]); # Robert Israel, Jun 01 2020
  • Mathematica
    f[n_] := Union[ IntegerQ /@ Drop[ n/FromDigits /@ Permutations[IntegerDigits[n]], 1]][[ -1]]; Select[ Range[ 9015], Mod[ #, 10] != 0 && f[ # ] == True &] (* Robert G. Wilson v, Jun 23 2004 *)

Extensions

Edited, corrected and extended by Robert G. Wilson v, Jun 23 2004