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.

A096199 Numbers such that in binary representation the length is a multiple of the number of ones.

Original entry on oeis.org

1, 2, 3, 4, 7, 8, 9, 10, 12, 15, 16, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 44, 48, 49, 50, 52, 56, 63, 64, 127, 128, 129, 130, 132, 135, 136, 139, 141, 142, 144, 147, 149, 150, 153, 154, 156, 160, 163, 165, 166, 169, 170, 172, 177, 178, 180, 184, 192, 195, 197
Offset: 1

Views

Author

Reinhard Zumkeller, Jul 26 2004

Keywords

Comments

A070939(a(n)) mod A000120(a(n)) = 0;
A000079 and A000225 (> 0) are subsequences.

Examples

			400 -> '110010000' with 3 binary ones and length = 9 = 3*3, therefore 400 is a term.
		

Crossrefs

Programs

  • Maple
    q:= n-> (l-> irem(nops(l), add(i, i=l))=0)(Bits[Split](n)):
    select(q, [$1..200])[];  # Alois P. Heinz, Feb 04 2022
  • Mathematica
    lmnQ[n_]:=Module[{idn2=IntegerDigits[n,2]},Divisible[Length[idn2],Count[ idn2,1]]]; Select[Range[200],lmnQ] (* Harvey P. Dale, Jul 27 2019 *)
  • Perl
    $cnt=1;foreach $n(1..100_000){$_=sprintf ("%b",$n); print $cnt++," $n\n" unless (length)%s/1//g;}