A169884 Numbers consisting of either all even digits or just 5's and 0's.

0, 2, 4, 5, 6, 8, 20, 22, 24, 26, 28, 40, 42, 44, 46, 48, 50, 55, 60, 62, 64, 66, 68, 80, 82, 84, 86, 88, 200, 202, 204, 206, 208, 220, 222, 224, 226, 228, 240, 242, 244, 246, 248, 260, 262, 264, 266, 268, 280, 282, 284, 286, 288, 400, 402, 404, 406

Offset

1,2

Comments

These are all the divisors of zero in carryless arithmetic mod 10. E.g. 5 * 44 = 0.

Links

Table of n, a(n) for n=1..57.

David Applegate, Marc LeBrun and N. J. A. Sloane, Carryless Arithmetic (I): The Mod 10 Version.

Index entries for 10-automatic sequences.

Index entries for sequences related to carryless arithmetic

Mathematica

With[{upto=410}, Select[Union[Join[Select[Range[upto], And@@EvenQ[ IntegerDigits[#]]&], FromDigits/@Tuples[{5, 0}, Ceiling[Log[ 10, upto]]]]], #<=upto&]] (* Harvey P. Dale, Aug 05 2011 *)

Crossrefs

Cf. A004520, A059729, A168294, A168541, A169885, A169886, A169887.

Sequence in context: A326703 A244008 A104704 * A341260 A072726 A343585

Adjacent sequences: A169881 A169882 A169883 * A169885 A169886 A169887

Keyword

nonn,base,easy

Author

David Applegate, Marc LeBrun and N. J. A. Sloane, Jul 06 2010

Status

approved